Earth Observations taken by the Expedition 20 crew

NASA Image and Video Library

2009-08-05

ISS020-E-028123 (5 Aug. 2009) --- Mount Hood, Oregon is featured in this image photographed by an Expedition 20 crew member on the International Space Station. Mount Hood is located within the Cascade Range of the western United States, and is the highest peak (3,426 m) in Oregon. The Cascade Range is characterized by a line of volcanoes associated with a slab of oceanic crust that is subducting, or descending underneath, the westward moving continental crust of North America. Magma generated by the subduction process rises upward through the crust and feeds a line of active volcanoes that extends from northern California in the United States to southern British Columbia in Canada. While hot springs and steam vents are still active on Mount Hood, the last eruption from the volcano occurred in 1866. The volcano is considered dormant, but still actively monitored. Separate phases of eruptive activity produced pyroclastic flows and lahars ? mudflows ? that carried erupted materials down all of the major rivers draining the volcano. Gray volcanic deposits extend southwards along the banks of the White River (upper right), and form several prominent ridges along the southeast to southwest flanks of the volcano. The deposits contrast sharply with the green vegetated lower flanks of the volcano. The Mount Hood stratovolcano ? a typically cone-shaped volcanic structure formed by interlayered lava flows and explosive eruption deposits ? hosts twelve mapped glaciers along its upper flanks (center). Like other glaciers in the Pacific Northwest, the Hood glaciers have been receding due to global warming, and have lost an estimated 61 percent of their volume over the past century. The predicted loss of glacial meltwater under future warming scenarios will have significant effects on regional hydrology and water supplies.

Plenty of Deep Long-Period Earthquakes Beneath Cascade Volcanoes

NASA Astrophysics Data System (ADS)

Nichols, M. L.; Malone, S. D.; Moran, S. C.; Thelen, W. A.; Vidale, J. E.

2009-12-01

The Pacific Northwest Seismic Network (PNSN) records and locates earthquakes within Washington and Oregon, including those occurring at 10 Cascade volcanic centers. In an earlier study (Malone and Moran, EOS 1997), a total of 11 deep long-period (DLP) earthquakes were reported beneath 3 Washington volcanoes. They are characterized by emergent P- and S- arrivals, long and ringing codas, and contain most of their energy below 5 Hz. DLP earthquakes are significant because they have been observed to occur prior to or in association with eruptions at several volcanoes, and as a result are inferred to represent movement of deep-seated magma and associated fluids in the mid-to-lower crust. To more thoroughly characterize DLP occurrence in Washington and Oregon, we employed a two-step algorithm to systematically search the PNSN’s earthquake catalogue for DLP events occurring between 1980 and 2008. In the first step we applied a spectral ratio test to the demeaned and tapered triggered event waveforms to distinguish long-period events from the more common higher frequency volcano-tectonic and regional tectonic earthquakes. In the second step we visually analyzed waveforms of the flagged long-period events to distinguish DLP earthquakes from long-period rockfalls, explosions, shallow low-frequency events, and glacier quakes. We identified 56 DLP earthquakes beneath 7 Cascade volcanic centers. Of these, 31 occurred at Mount Baker, where the background flux of magmatic gases is greater than at the other volcanoes in our study. The other 6 volcanoes with DLPs (counts in parentheses) are Glacier Peak (5), Mount Rainier (9), Mount St. Helens (9), Mount Hood (1), Three Sisters (1), and Crater Lake (1). No DLP events were identified beneath Mount Adams, Mount Jefferson, or Newberry Volcano. The events are 10-40 km deep and have an average magnitude of around 1.5 (Mc), with both the largest and deepest DLPs occurring beneath Mount Baker. Cascade DLP earthquakes occur mostly as single events, although there are a few instances where two consecutive DLPs occur within seconds to hours of each other. None of the DLP earthquakes have been associated with anomalous activity at any Cascade volcano, including the 1980-86 and 2004-08 eruptive periods at Mount St. Helens.

Characterizing and comparing seismicity at Cascade Range (USA) volcanoes

NASA Astrophysics Data System (ADS)

Moran, S. C.; Thelen, W. A.

2010-12-01

The Cascade Range includes 13 volcanic systems across Washington, Oregon, and northern California that are considered to have the potential to erupt at any time, including two that have erupted in the last 100 years (Mount St. Helens (MSH) and Lassen Peak). We investigated how seismicity compares among these volcanoes, and whether the character of seismicity (rate, type, style of occurrence over time, etc.) is related to eruptive activity at the surface. Seismicity at Cascade volcanoes has been monitored by seismic networks of variable apertures, station densities, and lengths of operation, which makes a direct comparison of seismicity among volcanoes somewhat problematic. Here we present results of two non-network-dependent approaches to making such seismicity comparisons. In the first, we used network geometry and a grid-search method to compute the minimum magnitude required for a network to locate an earthquake (“theoretical location threshold”, defined as an event recorded on at least 4 stations with gap of <135o) for each volcano out to 7 km. We then selected earthquakes with magnitudes greater than the highest theoretical location threshold determined for any Cascade volcano. To account for improving network densities with time, we used M 2.1 (location threshold for the Three Sisters 1980s-90s network) for 1987-1999 and M 1.6 (threshold for the Crater Lake 2000s network) for 2000-2010. In order to include only background seismicity, we excluded earthquakes occurring at any volcano during the 2004-2008 MSH eruption. We found that Mount Hood, Lassen Peak, and MSH had the three highest seismicity rates over that period, with Mount Hood, Medicine Lake volcano, and MSH having the three highest cumulative seismic energy releases. The Medicine Lake energy release is dominated by a single swarm in September 1988; if that swarm is removed, then Lassen would have the third-highest cumulative seismic energy release. For the second comparison, we determined the degree of “swarminess” for seismicity at each volcano. We first determined the background rate of locatable earthquakes (no selection criteria were applied) within 7 km of each volcanic center, and then identified days during which the rate of seismicity was 2σ or more above the background rate. Above-background days were linked together into one swarm if they occurred within 5 days of each other. We found that seismicity dominantly occurs in swarms (>60% of located earthquakes) at Mount Hood, Three Sisters, Medicine Lake, and Lassen Peak, is mixed at Mount Rainier (46%), and dominantly does not occur in swarms (<40%) at MSH (non-eruptive periods only) and Mount Shasta. These comparisons show no obvious relationship with recency of eruptive activity, with the possible exception that volcanoes with the most recent eruptions have the highest background seismicity levels.

Tilt networks of Mount Shasta and Lassen Peak, California

USGS Publications Warehouse

Dzurisin, Daniel; Johnson, Daniel J.; Murray, T.L.; Myers, Barbara

1982-01-01

In response to recent eruptions at Mount St. Helens and with support from the USGS Volcanic Hazards Program, the Cascades Volcano Observatory (CVO) has initiated a program to monitor all potentially-active volcanoes of the Cascade Range. As part of that effort, we installed tilt networks and obtained baseline measurements at Mount Shasta and Lassen Peak, California during July 1981. At the same time, baseline electronic distance measurements (EDM) were made and fumarole surveys were conducted by other crews from CVO. Annual surveys are planned initially, with subsequent visits as conditions warrant. These geodetic and geochemical measurements supplement a program of continuous seismic monitoring of Cascade volcanoes by the USGS Office of Earthquake Studies in cooperation with local universities. Other tilt networks were established at Mount Baker in 1975 and at Mount St. Helens in 1981. EDM networks were established at Mount Baker in 1975, Mount St. Helens in 1980, and Crater Lake in 1981. Additional tilt and/or EDM networks are planned for Mount Rainier, Mount Hood, Glacier Peak, Three Sisters, and Crater Lake as funds permit.

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

ERIC Educational Resources Information Center

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

1996-01-01

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

Volcano hazards assessment for the Lassen region, northern California

USGS Publications Warehouse

Clynne, Michael A.; Robinson, Joel E.; Nathenson, Manuel; Muffler, L.J. Patrick

2012-01-01

The Lassen region of the southernmost Cascade Range is an active volcanic area. At least 70 eruptions have occurred in the past 100,000 years, including 3 in the past 1,000 years, most recently in 1915. The record of past eruptions and the present state of the underlying magmatic and hydrothermal systems make it clear that future eruptions within the Lassen Volcanic Center are very likely. Although the annual probability of an eruption is small, the consequences of some types of eruptions could be severe. Compared to those of a typical Cascade composite volcano, eruptive vents at Lassen Volcanic Center and the surrounding area are widely dispersed, extending in a zone about 50 km wide from the southern boundary of Lassen Volcanic National Park north to the Pit River. This report presents a discussion of volcanic and other geologic hazards in the Lassen area and delineates hazards zones for different types of volcanic activity. Owing to its presence in a national park with significant visitorship, its explosive behavior, and its proximity to regional infrastructure, the Lassen Volcanic Center has been designated a "high threat volcano" in the U.S. Geological Survey National Volcano Early Warning System assessment. Volcanic eruptions are typically preceded by seismic activity and ground deformation, and the Lassen area has a network of seismometers and Global Positioning System stations in place to monitor for early warning of volcanic activity.

Seismicity of Cascade Volcanoes: Characterization and Comparison

NASA Astrophysics Data System (ADS)

Thelen, W. A.

2016-12-01

Here we summarize and compare the seismicity around each of the Very High Threat Volcanoes of the Cascade Range of Washington, Oregon and California as defined by the National Volcanic Early Warning System (NVEWS) threat assessment (Ewert et al., 2005). Understanding the background seismic activity and processes controlling it is critical for assessing changes in seismicity and their implications for volcanic hazards. Comparing seismicity at different volcanic centers can help determine what critical factors or processes affect the observed seismic behavior. Of the ten Very High Threat Volcanoes in the Cascade Range, five volcanoes are consistently seismogenic when considering earthquakes within 10 km of the volcanic center or caldera edge (Mount Rainier, Mount St. Helens, Mount Hood, Newberry Caldera, Lassen Volcanic Center). Other Very High Threat volcanoes (South Sister, Mount Baker, Glacier Peak, Crater Lake and Mount Shasta) have comparatively low rates of seismicity and not enough recorded earthquakes to calculate catalog statistics. Using a swarm definition of 3 or more earthquakes occurring in a day with magnitudes above the largest of the network's magnitude of completenesses (M 0.9), we find that Lassen Volcanic Center is the "swarmiest" in terms of percent of seismicity occurring in swarms, followed by Mount Hood, Mount St. Helens and Rainier. The predominance of swarms at Mount Hood may be overstated, as much of the seismicity is occurring on surrounding crustal faults (Jones and Malone, 2005). Newberry Caldera has a relatively short record of seismicity since the permanent network was installed in 2011, however there have been no swarms detected as defined here. Future work will include developing discriminates for volcanic versus tectonic seismicity to better filter the seismic catalog and more precise binning of depths at some volcanoes so that we may better consider different processes. Ewert J. W., Guffanti, M. and Murray, T. L. (2005). An Assessment of Volcanic Threat and Monitoring Capabilities in the United States: Framework for a National Volcano Early Warning System, USGS Open File Report 2005-1164, 62 pp. Jones, J., & Malone, S. D. (2005). Mount hood earthquake activity: Volcanic or tectonic origins? Bulletin Of The Seismological Society Of America, 95(3), 818-832.

The New USGS Volcano Hazards Program Web Site

NASA Astrophysics Data System (ADS)

Venezky, D. Y.; Graham, S. E.; Parker, T. J.; Snedigar, S. F.

2008-12-01

The U.S. Geological Survey's (USGS) Volcano Hazard Program (VHP) has launched a revised web site that uses a map-based interface to display hazards information for U.S. volcanoes. The web site is focused on better communication of hazards and background volcano information to our varied user groups by reorganizing content based on user needs and improving data display. The Home Page provides a synoptic view of the activity level of all volcanoes for which updates are written using a custom Google® Map. Updates are accessible by clicking on one of the map icons or clicking on the volcano of interest in the adjacent color-coded list of updates. The new navigation provides rapid access to volcanic activity information, background volcano information, images and publications, volcanic hazards, information about VHP, and the USGS volcano observatories. The Volcanic Activity section was tailored for emergency managers but provides information for all our user groups. It includes a Google® Map of the volcanoes we monitor, an Elevated Activity Page, a general status page, information about our Volcano Alert Levels and Aviation Color Codes, monitoring information, and links to monitoring data from VHP's volcano observatories: Alaska Volcano Observatory (AVO), Cascades Volcano Observatory (CVO), Long Valley Observatory (LVO), Hawaiian Volcano Observatory (HVO), and Yellowstone Volcano Observatory (YVO). The YVO web site was the first to move to the new navigation system and we are working on integrating the Long Valley Observatory web site next. We are excited to continue to implement new geospatial technologies to better display our hazards and supporting volcano information.

Chronology and References of Volcanic Eruptions and Selected Unrest in the United States, 1980-2008

USGS Publications Warehouse

Diefenbach, Angela K.; Guffanti, Marianne; Ewert, John W.

2009-01-01

The United States ranks as one of the top countries in the world in the number of young, active volcanoes within its borders. The United States, including the Commonwealth of the Northern Mariana Islands, is home to approximately 170 geologically active (age <10,000 years) volcanoes. As our review of the record shows, 30 of these volcanoes have erupted since 1980, many repeatedly. In addition to producing eruptions, many U.S. volcanoes exhibit periods of anomalous activity, unrest, that do not culminate in eruptions. Monitoring volcanic activity in the United States is the responsibility of the U.S. Geological Survey (USGS) Volcano Hazards Program (VHP) and is accomplished with academic, Federal, and State partners. The VHP supports five Volcano Observatories - the Alaska Volcano Observatory (AVO), Cascades Volcano Observatory (CVO), Yellowstone Volcano Observatory (YVO), Long Valley Observatory (LVO), and Hawaiian Volcano Observatory (HVO). With the exception of HVO, which was established in 1912, the U.S. Volcano Observatories have been established in the past 27 years in response to specific volcanic eruptions or sustained levels of unrest. As understanding of volcanic activity and hazards has grown over the years, so have the extent and types of monitoring networks and techniques available to detect early signs of anomalous volcanic behavior. This increased capability is providing us with a more accurate gauge of volcanic activity in the United States. The purpose of this report is to (1) document the range of volcanic activity that U.S. Volcano Observatories have dealt with, beginning with the 1980 eruption of Mount St. Helens, (2) describe some overall characteristics of the activity, and (3) serve as a quick reference to pertinent published literature on the eruptions and unrest documented in this report.

Volcano hazards program in the United States

USGS Publications Warehouse

Tilling, R.I.; Bailey, R.A.

1985-01-01

Volcano monitoring and volcanic-hazards studies have received greatly increased attention in the United States in the past few years. Before 1980, the Volcanic Hazards Program was primarily focused on the active volcanoes of Kilauea and Mauna Loa, Hawaii, which have been monitored continuously since 1912 by the Hawaiian Volcano Observatory. After the reawakening and catastrophic eruption of Mount St. Helens in 1980, the program was substantially expanded as the government and general public became aware of the potential for eruptions and associated hazards within the conterminous United States. Integrated components of the expanded program include: volcanic-hazards assessment; volcano monitoring; fundamental research; and, in concert with federal, state, and local authorities, emergency-response planning. In 1980 the David A. Johnston Cascades Volcano Observatory was established in Vancouver, Washington, to systematically monitor the continuing activity of Mount St. Helens, and to acquire baseline data for monitoring the other, presently quiescent, but potentially dangerous Cascade volcanoes in the Pacific Northwest. Since June 1980, all of the eruptions of Mount St. Helens have been predicted successfully on the basis of seismic and geodetic monitoring. The largest volcanic eruptions, but the least probable statistically, that pose a threat to western conterminous United States are those from the large Pleistocene-Holocene volcanic systems, such as Long Valley caldera (California) and Yellowstone caldera (Wyoming), which are underlain by large magma chambers still potentially capable of producing catastrophic caldera-forming eruptions. In order to become better prepared for possible future hazards associated with such historically unpecedented events, detailed studies of these, and similar, large volcanic systems should be intensified to gain better insight into caldera-forming processes and to recognize, if possible, the precursors of caldera-forming eruptions. ?? 1985.

Late Holocene volcanism at Medicine Lake Volcano, northern California Cascades

USGS Publications Warehouse

Donnelly-Nolan, Julie M.; Champion, Duane E.; Grove, Timothy L.

2016-05-23

Late Holocene volcanism at Medicine Lake volcano in the southern Cascades arc exhibited widespread and compositionally diverse magmatism ranging from basalt to rhyolite. Nine well-characterized eruptions have taken place at this very large rear-arc volcano since 5,200 years ago, an eruptive frequency greater than nearly all other Cascade volcanoes. The lavas are widely distributed, scattered over an area of ~300 km2 across the >2,000-km2 volcano. The eruptions are radiocarbon dated and the ages are also constrained by paleomagnetic data that provide strong evidence that the volcanic activity occurred in three distinct episodes at ~1 ka, ~3 ka, and ~5 ka. The ~1-ka final episode produced a variety of compositions including west- and north-flank mafic flows interspersed in time with fissure rhyolites erupted tangential to the volcano’s central caldera, including the youngest and most spectacular lava flow at the volcano, the ~950-yr-old compositionally zoned Glass Mountain flow. At ~3 ka, a north-flank basalt eruption was followed by an andesite eruption 27 km farther south that contains quenched basalt inclusions. The ~5-ka episode produced two caldera-focused dacitic eruptions. Quenched magmatic inclusions record evidence of intrusions that did not independently reach the surface. The inclusions are present in five andesitic, dacitic, and rhyolitic host lavas, and were erupted in each of the three episodes. Compositional and mineralogic evidence from mafic lavas and inclusions indicate that both tholeiitic (dry) and calcalkaline (wet) parental magmas were present. Petrologic evidence records the operation of complex, multi-stage processes including fractional crystallization, crustal assimilation, and magma mixing. Experimental evidence suggests that magmas were stored at 3 to 6 km depth prior to eruption, and that both wet and dry parental magmas were involved in generating the more silicic magmas. The broad distribution of eruptive events and the relative accessibility and good exposure of lavas, combined with physical and petrologic evidence for multiple and varied mafic inputs, has created an unusual opportunity to understand the workings of this large magmatic system. A combined total of more than 25 intrusive and extrusive events are indicated for late Holocene time. Plutonic inclusions, some with ages as young as Holocene, were also brought to the surface in five of the eruptions. All eruptions took place along northwest- to northeast-trending alignments of vents, reflecting the overall east-west extensional tectonic environment. The interaction of tectonism and volcanism is a dominant influence at this subduction-related volcano, located where the west edge of the extensional Basin and Range Province impinges on the Cascades arc. Ongoing subsidence focused at the central caldera has been documented along with geophysical evidence for a small magma body. This evidence, combined with the frequency of eruptive and intrusive activity in late Holocene time, an active geothermal system, and intermittent long-period seismic events indicate that the volcano is likely to erupt again.

Field-trip guide to the geologic highlights of Newberry Volcano, Oregon

USGS Publications Warehouse

Jensen, Robert A.; Donnelly-Nolan, Julie M.

2017-08-09

Newberry Volcano and its surrounding lavas cover about 3,000 square kilometers (km2) in central Oregon. This massive, shield-shaped, composite volcano is located in the rear of the Cascades Volcanic Arc, ~60 km east of the Cascade Range crest. The volcano overlaps the northwestern corner of the Basin and Range tectonic province, known locally as the High Lava Plains, and is strongly influenced by the east-west extensional environment. Lava compositions range from basalt to rhyolite. Eruptions began about half a million years ago and built a broad composite edifice that has generated more than one caldera collapse event. At the center of the volcano is the 6- by 8-km caldera, created ~75,000 years ago when a major explosive eruption of compositionally zoned tephra led to caldera collapse, leaving the massive shield shape visible today. The volcano hosts Newberry National Volcanic Monument, which encompasses the caldera and much of the northwest rift zone where mafic eruptions occurred about 7,000 years ago. These young lava flows erupted after the volcano was mantled by the informally named Mazama ash, a blanket of volcanic ash generated by the eruption that created Crater Lake about 7,700 years ago. This field trip guide takes the visitor to a variety of easily accessible geologic sites in Newberry National Volcanic Monument, including the youngest and most spectacular lava flows. The selected sites offer an overview of the geologic story of Newberry Volcano and feature a broad range of lava compositions. Newberry’s most recent eruption took place about 1,300 years ago in the center of the caldera and produced tephra and lava of rhyolitic composition. A significant mafic eruptive event occurred about 7,000 years ago along the northwest rift zone. This event produced lavas ranging in composition from basalt to andesite, which erupted over a distance of 35 km from south of the caldera to Lava Butte where erupted lava flowed west to temporarily block the Deschutes River. Because of Newberry Volcano’s proximity to populated areas, the presence of hot springs within the caldera, and the long and recent history of eruptive activity (including explosive activity), the U.S. Geological Survey installed monitoring equipment on the volcano. A recent geophysical study indicates the presence of magma at 3 to 5 km beneath the caldera.The writing of this guide was prompted by a field trip to Crater Lake and Newberry Volcano organized in conjunction with the August 2017 IAVCEI quadrennial meeting in Portland, Oregon. Both field trip guides are available online. These two volcanoes were grouped in a single field trip because they are two of the few Cascades volcanoes that have generated calderas and significant related tephra deposits.

Late Pleistocene and Holocene Geology and Hazards at Glacier Peak Volcano, Washington

NASA Astrophysics Data System (ADS)

Vallance, J. W.; Van Eaton, A. R.; Ramsey, D. W.

2015-12-01

Recent fieldwork, improved radiocarbon dating, and mapping on recently acquired LiDAR base have better delineated timing, frequency, and style of volcanism at Glacier Peak. The work shows that, after Mount St. Helens, Glacier Peak is one of the most frequently active Cascade volcanoes. The volcano has erupted multiple times 13-14 ka, 5­-7 ka, 1-2.5 ka, and perhaps as recently as a few hundred years ago. The plinian eruptions of ~13.5 ka were much more voluminous than those of Mount St. Helens in 1980 and show that Glacier Peak is among the most explosive of Cascade volcanoes. These eruptions dispersed ash fallout hundreds of kilometers downwind in Idaho, Montana and Wyoming; produced a partly welded ignimbrite and a small debris avalanche; and caused lahars and flooding far across Puget Sound lowland. Numerous more recent eruptions during the periods 5-7 ka and 1-2.5 ka extruded lava domes whose hot rock avalanched across snow and ice to produce pyroclastic flows and lahars. These eruptions dispersed ash tens of to a hundred or more kilometers downwind. Resulting lahars and floods inundated as far as Puget Sound lowland. Glacier Peak is remote and hidden from most areas of the densely populated Puget Sound lowland; hence, it gets less attention than other prominent Cascade volcanoes like Mounts Rainier, Baker, and St. Helens. Despite its remote location, Glacier Peak poses substantial hazard because even small eruptions on ice-clad volcanoes can have devastating consequences. Distal threats include hazard to air traffic owing to ash plumes. Lahars and potential long-term sedimentation and flooding downstream pose threats to communities near rivers along Skagit and Stillaguamish River drainages. Farther downstream, sedimentation is likely to decrease channel capacity, increasing likelihood of floods. Lava flows, pyroclastic flows, and debris avalanches will threaten hikers in the wilderness near Glacier Peak.

Volcano hazards in the Three Sisters region, Oregon

USGS Publications Warehouse

Scott, William E.; Iverson, R.M.; Schilling, S.P.; Fisher, B.J.

2001-01-01

Three Sisters is one of three potentially active volcanic centers that lie close to rapidly growing communities and resort areas in Central Oregon. Two types of volcanoes exist in the Three Sisters region and each poses distinct hazards to people and property. South Sister, Middle Sister, and Broken Top, major composite volcanoes clustered near the center of the region, have erupted repeatedly over tens of thousands of years and may erupt explosively in the future. In contrast, mafic volcanoes, which range from small cinder cones to large shield volcanoes like North Sister and Belknap Crater, are typically short-lived (weeks to centuries) and erupt less explosively than do composite volcanoes. Hundreds of mafic volcanoes scattered through the Three Sisters region are part of a much longer zone along the High Cascades of Oregon in which birth of new mafic volcanoes is possible. This report describes the types of hazardous events that can occur in the Three Sisters region and the accompanying volcano-hazard-zonation map outlines areas that could be at risk from such events. Hazardous events include landslides from the steep flanks of large volcanoes and floods, which need not be triggered by eruptions, as well as eruption-triggered events such as fallout of tephra (volcanic ash) and lava flows. A proximal hazard zone roughly 20 kilometers (12 miles) in diameter surrounding the Three Sisters and Broken Top could be affected within minutes of the onset of an eruption or large landslide. Distal hazard zones that follow river valleys downstream from the Three Sisters and Broken Top could be inundated by lahars (rapid flows of water-laden rock and mud) generated either by melting of snow and ice during eruptions or by large landslides. Slow-moving lava flows could issue from new mafic volcanoes almost anywhere within the region. Fallout of tephra from eruption clouds can affect areas hundreds of kilometers (miles) downwind, so eruptions at volcanoes elsewhere in the Cascade Range also contribute to volcano hazards in Central Oregon. This report is intended to aid scientists, government officials, and citizens as they work together to reduce the risk from volcano hazards through public education and emergency-response planning.

Digital Data for Volcano Hazards of the Three Sisters Region, Oregon

USGS Publications Warehouse

Schilling, S.P.; Doelger, S.; Scott, W.E.; Iverson, R.M.

2008-01-01

Three Sisters is one of three active volcanic centers that lie close to rapidly growing communities and resort areas in Central Oregon. The major composite volcanoes of this area are clustered near the center of the region and include South Sister, Middle Sister, and Broken Top. Additionally, hundreds of mafic volcanoes are scattered throughout the Three Sisters area. These range from small cinder cones to large shield volcanoes like North Sister and Belknap Crater. Hazardous events include landslides from the steep flanks of large volcanoes and floods, which need not be triggered by eruptions, as well as eruption-triggered events such as fallout of tephra (volcanic ash) and lava flows. A proximal hazard zone roughly 20 kilometers (12 miles) in diameter surrounding the Three Sisters and Broken Top could be affected within minutes of the onset of an eruption or large landslide. Distal hazard zones that follow river valleys downstream from the Three Sisters and Broken Top could be inundated by lahars (rapid flows of water-laden rock and mud) generated either by melting of snow and ice during eruptions or by large landslides. Slow-moving lava flows could issue from new mafic volcanoes almost anywhere within the region. Fallout of tephra from eruption clouds can affect areas hundreds of kilometers (miles) downwind, so eruptions at volcanoes elsewhere in the Cascade Range also contribute to volcano hazards in Central Oregon. Scientists at the Cascades Volcano Observatory created a geographic information system (GIS) data set which depicts proximal and distal lahar hazard zones as well as a regional lava flow hazard zone for Three Sisters (USGS Open-File Report 99-437, Scott and others, 1999). The various distal lahar zones were constructed from LaharZ software using 20, 100, and 500 million cubic meter input flow volumes. Additionally, scientists used the depositional history of past events in the Three Sisters Region as well as experience and judgment derived from the study of volcanoes to help construct the regional hazard zone.

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

USGS Publications Warehouse

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

2017-08-15

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

Crater Lake revealed

USGS Publications Warehouse

Ramsey, David W.; Dartnell, Peter; Bacon, Charles R.; Robinson, Joel E.; Gardner, James V.

2003-01-01

Around 500,000 people each year visit Crater Lake National Park in the Cascade Range of southern Oregon. Volcanic peaks, evergreen forests, and Crater Lake’s incredibly blue water are the park’s main attractions. Crater Lake partially fills the caldera that formed approximately 7,700 years ago by the eruption and subsequent collapse of a 12,000-foot volcano called Mount Mazama. The caldera-forming or climactic eruption of Mount Mazama drastically changed the landscape all around the volcano and spread a blanket of volcanic ash at least as far away as southern Canada.Prior to the climactic event, Mount Mazama had a 400,000 year history of cone building activity like that of other Cascade volcanoes such as Mount Shasta. Since the climactic eruption, there have been several less violent, smaller postcaldera eruptions within the caldera itself. However, relatively little was known about the specifics of these eruptions because their products were obscured beneath Crater Lake’s surface. As the Crater Lake region is still potentially volcanically active, understanding past eruptive events is important to understanding future eruptions, which could threaten facilities and people at Crater Lake National Park and the major transportation corridor east of the Cascades.Recently, the lake bottom was mapped with a high-resolution multibeam echo sounder. The new bathymetric survey provides a 2m/pixel view of the lake floor from its deepest basins virtually to the shoreline. Using Geographic Information Systems (GIS) applications, the bathymetry data can be visualized and analyzed to shed light on the geology, geomorphology, and geologic history of Crater Lake.

Digital Data for Volcano Hazards of the Mount Hood Region, Oregon

USGS Publications Warehouse

Schilling, S.P.; Doelger, S.; Scott, W.E.; Pierson, T.C.; Costa, J.E.; Gardner, C.A.; Vallance, J.W.; Major, J.J.

2008-01-01

Snow-clad Mount Hood dominates the Cascade skyline from the Portland metropolitan area to the wheat fields of Wasco and Sherman Counties. The mountain contributes valuable water, scenic, and recreational resources that help sustain the agricultural and tourist segments of the economies of surrounding cities and counties. Mount Hood is also one of the major volcanoes of the Cascade Range, having erupted repeatedly for hundreds of thousands of years, most recently during two episodes in the past 1,500 yr. The last episode ended shortly before the arrival of Lewis and Clark in 1805. When Mount Hood erupts again, it will severely affect areas on its flanks and far downstream in the major river valleys that head on the volcano. Volcanic ash may fall on areas up to several hundred kilometers downwind. The purpose of the volcano hazard report USGS Open-File Report 97-89 (Scott and others, 1997) is to describe the kinds of hazardous geologic events that have happened at Mount Hood in the past and to show which areas will be at risk when such events occur in the future. This data release contains the geographic information system (GIS) data layers used to produce the Mount Hood volcano hazard map in USGS Open-File Report 97-89. Both proximal and distal hazard zones were delineated by scientists at the Cascades Volcano Observatory and depict various volcano hazard areas around the mountain. A second data layer contains points that indicate estimated travel times of lahars.

Digital Data for Volcano Hazards from Mount Rainier, Washington, Revised 1998

USGS Publications Warehouse

Schilling, S.P.; Doelger, S.; Hoblitt, R.P.; Walder, J.S.; Driedger, C.L.; Scott, K.M.; Pringle, P.T.; Vallance, J.W.

2008-01-01

Mount Rainier at 4393 meters (14,410 feet) is the highest peak in the Cascade Range; a dormant volcano having glacier ice that exceeds that of any other mountain in the conterminous United States. This tremendous mass of rock and ice, in combination with great topographic relief, poses a variety of geologic hazards, both during inevitable future eruptions and during the intervening periods of repose. The volcano's past behavior is the best guide to possible future hazards. The written history (about A.D. 1820) of Mount Rainier includes one or two small eruptions, several small debris avalanches, and many small lahars (debris flows originating on a volcano). In addition, prehistoric deposits record the types, magnitudes, and frequencies of other events, and areas that were affected. Mount Rainier deposits produced since the latest ice age (approximately during the past 10,000 years) are well preserved. Studies of these deposits indicate we should anticipate potential hazards in the future. Some phenomena only occur during eruptions such as tephra falls, pyroclastic flows and surges, ballistic projectiles, and lava flows while others may occur without eruptive activity such as debris avalanches, lahars, and floods. The five geographic information system (GIS) volcano hazard data layers used to produce the Mount Rainier volcano hazard map in USGS Open-File Report 98-428 (Hoblitt and others, 1998) are included in this data set. Case 1, case 2, and case 3 layers were delineated by scientists at the Cascades Volcano Observatory and depict various lahar innundation zones around the mountain. Two additional layers delineate areas that may be affected by post-lahar sedimentation (postlahar layer) and pyroclastic flows (pyroclastic layer).

Attaining high-resolution eruptive histories for active arc volcanoes with argon geochronology

NASA Astrophysics Data System (ADS)

Calvert, A. T.

2012-04-01

Geochronology of active arc volcanoes commonly illuminates eruptive behavior over tens to hundreds of thousands of years, lengthy periods of repose punctuated by short eruptive episodes, and spatial and compositional changes with time. Despite the >1 Gyr half-life of 40K, argon geochronology is an exceptional tool for characterizing Pleistocene to Holocene eruptive histories and for placing constraints on models of eruptive behavior. Reliable 40Ar/39Ar ages of calc-alkaline arc rocks with rigorously derived errors small enough (± 500 to 3,000 years) to constrain eruptive histories are attainable using careful procedures. Sample selection and analytical work in concert with geologic mapping and stratigraphic studies are essential for determining reliable eruptive histories. Preparation, irradiation and spectrometric techniques have all been optimized to produce reliable, high-precision results. Examples of Cascade and Alaska/Aleutian eruptive histories illustrating duration of activity from single centers, eruptive episodicity, and spatial and compositional changes with time will be presented: (1) Mt. Shasta, the largest Cascade stratovolcano, has a 700,000-year history (Calvert and Christiansen, 2011 Fall AGU). A similar sized and composition volcano (Rainbow Mountain) on the Cascade axis was active 1200-950 ka. The eruptive center then jumped west 15 km to the south flank of the present Mt. Shasta and produced a stratovolcano from 700-450 ka likely rivaling today's Mt. Shasta. The NW portion of that edifice failed in an enormous (>30 km3) debris avalanche. Vents near today's active summit erupted 300-135 ka, then 60-15 ka. A voluminous, but short-lived eruptive sequence occurred at 11 ka, including a summit explosion producing a subplinian plume, followed by >60 km3 andesite-dacite Shastina domes and flows, then by the flank dacite Black Butte dome. Holocene domes and flows subsequently rebuilt the summit and flowed to the north and east. (2) Mt. Veniaminof on the Alaska Peninsula is a ~350 km3 tholeiitic arc volcano with basalt early in its history (~250 ka) and basaltic andesite to dacite currently. Chemical variation is due principally to crystallization differentiation with little or no evidence for crustal contamination. The smooth increase with time of Veniaminof's most silicic products chronicles the development of an intrusive complex, also reflected in granitoid blocks expelled during Holocene explosive eruptions (Bacon et al., 2007 Geology). (3) The Three Sisters in the central Oregon Cascades are a cluster of small volcanoes with remarkable chemical diversity (basalt to high silica rhyolite) that mainly erupted in a short interval between 40-15 ka. This eruptive interval was unusual in its chemical diversity beginning bimodal (basaltic andesite and rhyolite), progressing to dacite then andesite, and back to basaltic andesite. Over eighty percent of mapped units are dated, enabling time-series displays of the chemical and spatial evolution of the volcanic field (Calvert et al., 2010 Fall AGU).

Do Glaciers on Cascade Volcanoes Behave Differently Than Other Glaciers in the Region?

NASA Astrophysics Data System (ADS)

Riedel, J. L.; Ryane, C.; Osborn, J.; Davis, T.; Menounos, B.; Clague, J. J.; Koch, J.; Scott, K. M.; Reasoner, M.

2006-12-01

It has been suggested that glaciers on two stratovolcanoes in the Cascade Range of Washington state, Mt. Baker and Glacier Peak, achieved their maximum extent of the past 10,000 years during the early Holocene. These findings differ from most evidence in western North America, which indicates that Little Ice Age moraines represent the most extensive glacier advances of the Holocene. Significant early Holocene advances are difficult to reconcile with the documented warm, dry conditions at this time in western North America. Our data indicate that glaciers on these volcanoes responded similarly to Holocene climatic events as glaciers in other areas in Washington and British Columbia. Heavy winter accumulation and favorable hypsometry have been proposed as the explanations for the unusual behavior of glaciers on volcanoes compared to similar-sized glaciers elsewhere in the Cascade Range. However, glacier mass balance on the volcanoes is controlled by not only these factors, but also by glacier geometry, snow erosion and ablation. Accumulation zones of glaciers on isolated Cascade stratovolcanoes are high, but are narrow at the top. For example, the accumulation zone of Deming Glacier on the southwest side of Mt. Baker extends above 3000 m asl, but due to its wedge shape lies largely below 2500 m asl. Furthermore, glaciers on Mt. Baker and other symmetrical volcanoes have high ablation rates because they are not shaded, and south-southwest aspects are subject to erosion of snow by prevailing southwesterly winds. Modern glacier observations in the North Cascades quantify the important influence of aspect and snow erosion on glacier mass balance. For example, average equilibrium line altitude (ELA) of Easton Glacier on the south flank of Mt. Baker is 2160 m, whereas the ELA of a north-facing cirque glacier 25km to the east is 2040m. Our research at Mt. Baker contradicts the claim of extensive early Holocene advances on the south flank of the volcano. Tephra set SC, which has been radiocarbon dated to about 8850 14C yr old, is found on ridges that were previously mapped as moraines younger than the tephra. This relation indicates that "early Holocene" ridges are more than 8850 14C yr old, with their maximum age unconstrained. Most of the radial ridges previously mapped as moraines cannot be conclusively shown to be moraines; they could be lahar levees or diamict-covered bedrock ridges, which are common on Cascade stratovolcanoes. Our data indicate that the record of middle and late Holocene glaciation on Mt. Baker is similar, if not identical, to that reported from the British Columbia Coast Mountains. Consequently, there is no reason to believe that the history of Holocene glaciation on Cascade volcanoes is radically different than elsewhere in western North America.

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

NASA Astrophysics Data System (ADS)

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

2015-12-01

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

Snow and ice volume on Mount Spurr Volcano, Alaska, 1981

USGS Publications Warehouse

March, Rod S.; Mayo, Lawrence R.; Trabant, Dennis C.

1997-01-01

Mount Spurr (3,374 meters altitude) is an active volcano 130 kilometers west of Anchorage, Alaska, with an extensive covering of seasonal and perennial snow, and glaciers. Knowledge of the volume and distribution of snow and ice on a volcano aids in assessing hydrologic hazards such as floods, mudflows, and debris flows. In July 1981, ice thickness was measured at 68 locations on the five main glaciers of Mount Spurr: 64 of these measurements were made using a portable 1.7 megahertz monopulse ice-radar system, and 4 measurements were made using the helicopter altimeter where the glacier bed was exposed by ice avalanching. The distribution of snow and ice derived from these measurements is depicted on contour maps and in tables compiled by altitude and by drainage basins. Basal shear stresses at 20 percent of the measured locations ranged from 200 to 350 kilopascals, which is significantly higher than the 50 to 150 kilopascals commonly referred to in the literature as the 'normal' range for glaciers. Basal shear stresses higher than 'normal' have also been found on steep glaciers on volcanoes in the Cascade Range in the western United States. The area of perennial snow and ice coverage on Mount Spurr was 360 square kilometers in 1981, with an average thickness of 190?50 meters. Seasonal snow increases the volume about 1 percent and increases the area about 30 percent with a maximum in May or June. Runoff from Mount Spurr feeds the Chakachatna River and the Chichantna River (a tributary of the Beluga River). The Chakachatna River drainage contains 14 cubic kilometers of snow and ice and the Chichantna River drainage contains 53 cubic kilometers. The snow and ice volume on the mountain was 67?17 cubic kilometers, approximately 350 times more snow and ice than was on Mount St. Helens before its May 18, 1980, eruption, and 15 times more snow and ice than on Mount Rainier, the most glacierized of the measured volcanoes in the Cascade Range. On the basis of these relative quantities, hazard-producing glaciovolcanic phenomena at Mount Spurr could be significantly greater than similar phenomena at Cascade Volcanoes.

Digital Data for Volcano Hazards at Newberry Volcano, Oregon

USGS Publications Warehouse

Schilling, S.P.; Doelger, S.; Sherrod, D.R.; Mastin, L.G.; Scott, W.E.

2008-01-01

Newberry volcano is a broad shield volcano located in central Oregon, the product of thousands of eruptions, beginning about 600,000 years ago. At least 25 vents on the flanks and summit have been active during the past 10,000 years. The most recent eruption 1,300 years ago produced the Big Obsidian Flow. Thus, the volcano's long history and recent activity indicate that Newberry will erupt in the future. Newberry Crater, a volcanic depression or caldera has been the focus of Newberry's volcanic activity for at least the past 10,000 years. Newberry National Volcanic Monument, which is managed by the U.S. Forest Service, includes the caldera and extends to the Deschutes River. Newberry volcano is quiet. Local earthquake activity (seismicity) has been trifling throughout historic time. Subterranean heat is still present, as indicated by hot springs in the caldera and high temperatures encountered during exploratory drilling for geothermal energy. The report USGS Open-File Report 97-513 (Sherrod and others, 1997) describes the kinds of hazardous geologic events that might occur in the future at Newberry volcano. A hazard-zonation map is included to show the areas that will most likely be affected by renewed eruptions. When Newberry volcano becomes restless, the eruptive scenarios described herein can inform planners, emergency response personnel, and citizens about the kinds and sizes of events to expect. The geographic information system (GIS) volcano hazard data layers used to produce the Newberry volcano hazard map in USGS Open-File Report 97-513 are included in this data set. Scientists at the USGS Cascades Volcano Observatory created a GIS data layer to depict zones subject to the effects of an explosive pyroclastic eruption (tephra fallout, pyroclastic flows, and ballistics), lava flows, volcanic gasses, and lahars/floods in Paulina Creek. A separate GIS data layer depicts drill holes on the flanks of Newberry Volcano that were used to estimate the probability of coverage by future lava flows.

Digital Geologic Map Database of Medicine Lake Volcano, Northern California

NASA Astrophysics Data System (ADS)

Ramsey, D. W.; Donnelly-Nolan, J. M.; Felger, T. J.

2010-12-01

Medicine Lake volcano, located in the southern Cascades ~55 km east-northeast of Mount Shasta, is a large rear-arc, shield-shaped volcano with an eruptive history spanning nearly 500 k.y. Geologic mapping of Medicine Lake volcano has been digitally compiled as a spatial database in ArcGIS. Within the database, coverage feature classes have been created representing geologic lines (contacts, faults, lava tubes, etc.), geologic unit polygons, and volcanic vent location points. The database can be queried to determine the spatial distributions of different rock types, geologic units, and other geologic and geomorphic features. These data, in turn, can be used to better understand the evolution, growth, and potential hazards of this large, rear-arc Cascades volcano. Queries of the database reveal that the total area covered by lavas of Medicine Lake volcano, which range in composition from basalt through rhyolite, is about 2,200 km2, encompassing all or parts of 27 U.S. Geological Survey 1:24,000-scale topographic quadrangles. The maximum extent of these lavas is about 80 km north-south by 45 km east-west. Occupying the center of Medicine Lake volcano is a 7 km by 12 km summit caldera in which nestles its namesake, Medicine Lake. The flanks of the volcano, which are dotted with cinder cones, slope gently upward to the caldera rim, which reaches an elevation of nearly 2,440 m. Approximately 250 geologic units have been mapped, only half a dozen of which are thin surficial units such as alluvium. These volcanic units mostly represent eruptive events, each commonly including a vent (dome, cinder cone, spatter cone, etc.) and its associated lava flow. Some cinder cones have not been matched to lava flows, as the corresponding flows are probably buried, and some flows cannot be correlated with vents. The largest individual units on the map are all basaltic in composition, including the late Pleistocene basalt of Yellowjacket Butte (296 km2 exposed), the largest unit on the map, whose area is partly covered by a late Holocene andesite flow. Silicic lava flows are mostly confined to the main edifice of the volcano, with the youngest rhyolite flows found in and near the summit caldera, including the rhyolitic Little Glass Mountain (~1,000 yr B.P.) and Glass Mountain (~950 yr B.P.) flows, which are the youngest eruptions at Medicine Lake volcano. In postglacial time, 17 eruptions have added approximately 7.5 km3 to the volcano’s total estimated volume of 600 km3, which may be the largest by volume among Cascade Range volcanoes. The volcano has erupted nine times in the past 5,200 years, a rate more frequent than has been documented at all other Cascade volcanoes except Mount St. Helens.

Mount Rainier: A decade volcano

NASA Astrophysics Data System (ADS)

Swanson, Donald A.; Malone, Stephen D.; Samora, Barbara A.

Mount Rainier, the highest (4392 m) volcano in the Cascade Range, towers over a population of more than 2.5 million in the Seattle-Tacoma metropolitan area, and its drainage system via the Columbia River potentially affects another 500,000 residents of southwestern Washington and northwestern Oregon (Figure 1). Mount Rainier is the most hazardous volcano in the Cascades in terms of its potential for magma-water interaction and sector collapse. Major eruptions, or debris flows even without eruption, pose significant dangers and economic threats to the region. Despite such hazard and risk, Mount Rainier has received little study; such important topics as its petrologic and geochemical character, its proximal eruptive history, its susceptibility to major edifice failure, and its development over time have been barely investigated. This situation may soon change because of Mount Rainier's recent designation as a “Decade Volcano.”

Eruptions of Lassen Peak, California, 1914 to 1917

USGS Publications Warehouse

Clynne, Michael A.; Christiansen, Robert L.; Felger, Tracey J.; Stauffer, Peter H.; Hendley, James W.

1999-01-01

On May 22, 1915, an explosive eruption at Lassen Peak, California, the southernmost active volcano in the Cascade Range, devastated nearby areas and rained volcanic ash as far away as 200 miles to the east. This explosion was the most powerful in a 1914–17 series of eruptions that were the last to occur in the Cascades before the 1980 eruption of Mount St. Helens, Washington. Recent work by scientists with the U.S. Geological Survey (USGS) in cooperation with the National Park Service is shedding new light on these eruptions.

Alaska volcanoes guidebook for teachers

USGS Publications Warehouse

Adleman, Jennifer N.

2011-01-01

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

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

USGS Publications Warehouse

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

2013-01-01

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

Glacier volume estimation of Cascade Volcanoes—an analysis and comparison with other methods

USGS Publications Warehouse

Driedger, Carolyn L.; Kennard, P.M.

1986-01-01

During the 1980 eruption of Mount St. Helens, the occurrence of floods and mudflows made apparent a need to assess mudflow hazards on other Cascade volcanoes. A basic requirement for such analysis is information about the volume and distribution of snow and ice on these volcanoes. An analysis was made of the volume-estimation methods developed by previous authors and a volume estimation method was developed for use in the Cascade Range. A radio echo-sounder, carried in a backpack, was used to make point measurements of ice thickness on major glaciers of four Cascade volcanoes (Mount Rainier, Washington; Mount Hood and the Three Sisters, Oregon; and Mount Shasta, California). These data were used to generate ice-thickness maps and bedrock topographic maps for developing and testing volume-estimation methods. Subsequently, the methods were applied to the unmeasured glaciers on those mountains and, as a test of the geographical extent of applicability, to glaciers beyond the Cascades having measured volumes. Two empirical relationships were required in order to predict volumes for all the glaciers. Generally, for glaciers less than 2.6 km in length, volume was found to be estimated best by using glacier area, raised to a power. For longer glaciers, volume was found to be estimated best by using a power law relationship, including slope and shear stress. The necessary variables can be estimated from topographic maps and aerial photographs.

A magmatic model of Medicine Lake Volcano, California ( USA).

USGS Publications Warehouse

Donnelly-Nolan, J. M.

1988-01-01

Medicine Lake volcano is a Pleistocene and Holocene shield volcano of the southern Cascade Range. It is located behind the main Cascade arc in an extensional tectonic setting where high-alumina basalt is the most commonly erupted lava. This basalt is parental to the higher-silica calc-alkaline and tholeiitic lavas that make up the bulk of the shield. The presence of late Holocene, chemically identical rhyolites on opposite sides of the volcano led to hypotheses of a large shallow silicic magma chamber and of a small, deep chamber that fed rhyolites to the surface via cone sheets. Subsequent geophysical work has been unable to identify a large silicic magma body, and instead a small one has apparently been recognized. Some geologic data support the geophysical results. Tectonic control of vent alignments and the dominance of mafic eruptions both in number of events and volume throughout the history of the volcano indicate that no large silicic magma reservoir exists. Instead, a model is proposed that includes numerous dikes, sills and small magma bodies, most of which are too small to be recognized by present geophysical methods.-Author

Eruptions of Hawaiian volcanoes - Past, present, and future

USGS Publications Warehouse

Tilling, Robert I.; Heliker, Christina; Swanson, Donald A.

2010-01-01

Viewing an erupting volcano is a memorable experience, one that has inspired fear, superstition, worship, curiosity, and fascination since before the dawn of civilization. In modern times, volcanic phenomena have attracted intense scientific interest, because they provide the key to understanding processes that have created and shaped more than 80 percent of the Earth's surface. The active Hawaiian volcanoes have received special attention worldwide because of their frequent spectacular eruptions, which often can be viewed and studied with relative ease and safety. In January 1987, the Hawaiian Volcano Observatory (HVO), located on the rim of Kilauea Volcano, celebrated its 75th Anniversary. In honor of HVO's Diamond Jubilee, the U.S. Geological Survey (USGS) published Professional Paper 1350 (see list of Selected Readings, page 57), a comprehensive summary of the many studies on Hawaiian volcanism by USGS and other scientists through the mid-1980s. Drawing from the wealth of data contained in that volume, the USGS also published in 1987 the original edition of this general-interest booklet, focusing on selected aspects of the eruptive history, style, and products of two of Hawai'i's active volcanoes, Kilauea and Mauna Loa. This revised edition of the booklet-spurred by the approaching Centennial of HVO in January 2012-summarizes new information gained since the January 1983 onset of Kilauea's Pu'u 'O'o-Kupaianaha eruption, which has continued essentially nonstop through 2010 and shows no signs of letup. It also includes description of Kilauea's summit activity within Halema'uma'u Crater, which began in mid-March 2008 and continues as of this writing (late 2010). This general-interest booklet is a companion to the one on Mount St. Helens Volcano first published in 1984 and revised in 1990 (see Selected Readings). Together, these publications illustrate the contrast between the two main types of volcanoes: shield volcanoes, such as those in Hawai'i, which generally are nonexplosive; and composite volcanoes, such as Mount St. Helens in the Cascade Range, which are renowned for their explosive eruptions.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barrat, J.

Mount St. Helens' eruption has taught geologists invaluable lessons about how volcanoes work. Such information will be crucial in saving lives and property when other dormant volcanoes in the northwestern United States--and around the world--reawaken, as geologists predict they someday will. Since 1912, scientists at the U.S. Geological Survey's Hawaiian Volcano Observatory have pioneered the study of volcanoes through work on Mauna Loa and Kilauea volcanoes on the island of Hawaii. In Vancouver, Wash., scientists at the Survey's Cascades Volcano Observatory are studying the after-effects of Mount St. Helens' catalysmic eruption as well as monitoring a number of other now-dormantmore » volcanoes in the western United States. This paper briefly reviews the similarities and differences between the Hawaiian and Washington volcanoes and what these volcanoes are teaching the volcanologists.« less

Cascade Mountain Range in Oregon

USGS Publications Warehouse

Sherrod, David R.

2016-01-01

Along its Oregon segment, the Cascade Range is almost entirely volcanic in origin. The volcanoes and their eroded remnants are the visible magmatic expression of the Cascadia subduction zone, where the offshore Juan de Fuca tectonic plate is subducted beneath North America. Subduction occurs as two lithospheric plates collide, and an underthrusted oceanic plate is commonly dragged into the mantle by the pull of gravity, carrying ocean-bottom rock and sediment down to where heat and pressure expel water. As this water rises, it lowers the melting temperature in the overlying hot mantle rocks, thereby promoting melting. The molten rock supplies the volcanic arcs with heat and magma. Cascade Range volcanoes are part of the Ring of Fire, a popular term for the numerous volcanic arcs that encircle the Pacific Ocean.

Titanium dioxide in pyroclastic layers from volcanoes in the cascade range

USGS Publications Warehouse

Czamanske, G.K.; Porter, S.C.

1965-01-01

Rapid determinations of titanium dioxide have been made by x-ray emission techniques to evaluate the potentiality of using the TiO2 content of samples for checking field correlations and assisting in identification of pyroclastic units from Cascade volcanoes. Preliminary data suggest that the two most wide-spread units have characteristic ranges of TiO2 content and that other, less extensive layers have ranges which, though characteristic, often overlap the ranges of the more widespread layers. Relative to fresh samples, weathered samples from B and C soil horizons are enriched in TiO 2.

Thermal surveillance of Cascade Range volcanoes using ERTS-1 multispectral scanner, aircraft imaging systems, and ground-based data communication platforms

NASA Technical Reports Server (NTRS)

Friedman, J. D.; Frank, D. G.; Preble, D.; Painter, J. E.

1973-01-01

A combination of infrared images depicting areas of thermal emission and ground calibration points have proved to be particularly useful in plotting time-dependent changes in surface temperatures and radiance and in delimiting areas of predominantly convective heat flow to the earth's surface in the Cascade Range and on Surtsey Volcano, Iceland. In an integrated experiment group using ERTS-1 multispectral scanner (MSS) and aircraft infrared imaging systems in conjunction with multiple thermistor arrays, volcano surface temperatures are relayed daily to Washington via data communication platform (DCP) transmitters and ERTS-1. ERTS-1 MSS imagery has revealed curvilinear structures at Lassen, the full extent of which have not been previously mapped. Interestingly, the major surface thermal manifestations at Lassen are aligned along these structures, particularly in the Warner Valley.

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

NASA Astrophysics Data System (ADS)

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.

A sight "fearfully grand": eruptions of Lassen Peak, California, 1914 to 1917

USGS Publications Warehouse

Clynne, Michael A.; Christiansen, Robert L.; Stauffer, Peter H.; Hendley, James W.; Bleick, Heather A.

2014-01-01

On May 22, 1915, a large explosive eruption at the summit of Lassen Peak, California, the southernmost active volcano in the Cascade Range, devastated nearby areas and rained volcanic ash as far away as 280 miles to the east. This explosion was the most powerful in a series of eruptions during 1914–17 that were the last to occur in the Cascade Range before the 1980 eruption of Mount St. Helens, Washington. A century after the Lassen eruptions, work by U.S. Geological Survey (USGS) scientists in cooperation with the National Park Service is shedding new light on these events.

Deep long-period earthquakes beneath Washington and Oregon volcanoes

NASA Astrophysics Data System (ADS)

Nichols, M. L.; Malone, S. D.; Moran, S. C.; Thelen, W. A.; Vidale, J. E.

2011-03-01

Deep long-period (DLP) earthquakes are an enigmatic type of seismicity occurring near or beneath volcanoes. They are commonly associated with the presence of magma, and found in some cases to correlate with eruptive activity. To more thoroughly understand and characterize DLP occurrence near volcanoes in Washington and Oregon, we systematically searched the Pacific Northwest Seismic Network (PNSN) triggered earthquake catalog for DLPs occurring between 1980 (when PNSN began collecting digital data) and October 2009. Through our analysis we identified 60 DLPs beneath six Cascade volcanic centers. No DLPs were associated with volcanic activity, including the 1980-1986 and 2004-2008 eruptions at Mount St. Helens. More than half of the events occurred near Mount Baker, where the background flux of magmatic gases is greatest among Washington and Oregon volcanoes. The six volcanoes with DLPs (counts in parentheses) are Mount Baker (31), Glacier Peak (9), Mount Rainier (9), Mount St. Helens (9), Three Sisters (1), and Crater Lake (1). No DLPs were identified beneath Mount Adams, Mount Hood, Mount Jefferson, or Newberry Volcano, although (except at Hood) that may be due in part to poorer network coverage. In cases where the DLPs do not occur directly beneath the volcanic edifice, the locations coincide with large structural faults that extend into the deep crust. Our observations suggest the occurrence of DLPs in these areas could represent fluid and/or magma transport along pre-existing tectonic structures in the middle crust.

Deep long-period earthquakes beneath Washington and Oregon volcanoes

USGS Publications Warehouse

Nichols, M.L.; Malone, S.D.; Moran, S.C.; Thelen, W.A.; Vidale, J.E.

2011-01-01

Deep long-period (DLP) earthquakes are an enigmatic type of seismicity occurring near or beneath volcanoes. They are commonly associated with the presence of magma, and found in some cases to correlate with eruptive activity. To more thoroughly understand and characterize DLP occurrence near volcanoes in Washington and Oregon, we systematically searched the Pacific Northwest Seismic Network (PNSN) triggered earthquake catalog for DLPs occurring between 1980 (when PNSN began collecting digital data) and October 2009. Through our analysis we identified 60 DLPs beneath six Cascade volcanic centers. No DLPs were associated with volcanic activity, including the 1980-1986 and 2004-2008 eruptions at Mount St. Helens. More than half of the events occurred near Mount Baker, where the background flux of magmatic gases is greatest among Washington and Oregon volcanoes. The six volcanoes with DLPs (counts in parentheses) are Mount Baker (31), Glacier Peak (9), Mount Rainier (9), Mount St. Helens (9), Three Sisters (1), and Crater Lake (1). No DLPs were identified beneath Mount Adams, Mount Hood, Mount Jefferson, or Newberry Volcano, although (except at Hood) that may be due in part to poorer network coverage. In cases where the DLPs do not occur directly beneath the volcanic edifice, the locations coincide with large structural faults that extend into the deep crust. Our observations suggest the occurrence of DLPs in these areas could represent fluid and/or magma transport along pre-existing tectonic structures in the middle crust. ?? 2010 Elsevier B.V.

Cascade Mtns. Oregon

NASA Image and Video Library

2002-04-19

The ground near one of the long-dormant Three Sisters volcanoes in the Cascade Mountains of west-central Oregon has risen approximately 10centimeters in a 10-by-20-km parcel since 1996, meaning that magma or underground lava is slowly flowing into the area, according to a research team from the U.S. Geological Survey. The Three Sisters area -- which contains five volcanoes -- is only about 170 miles from Mount St. Helens, which erupted in 1980. Both are part of the Cascades Range, a line of 27volcanoes stretching from British Columbia in Canada to northern California. This perspective view was created by draping a simulated natural color ASTER image over digital topography from the U.S. Geological Survey National Elevation Dataset. This image was acquired on May 28, 2000 by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite. With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER will image Earth for the next 6 years to map and monitor the changing surface of our planet. http://photojournal.jpl.nasa.gov/catalog/PIA03492

Overview for geologic field-trip guides to Mount Mazama, Crater Lake Caldera, and Newberry Volcano, Oregon

USGS Publications Warehouse

Bacon, Charles R.; Donnelly-Nolan, Julie M.; Jensen, Robert A.; Wright, Heather M.

2017-08-16

These field-trip guides were written for the occasion of the International Association of Volcanology and Chemistry of the Earth’s Interior (IAVCEI) quadrennial scientific assembly in Portland, Oregon, in August 2017. The guide to Mount Mazama and Crater Lake caldera is an updated and expanded version of the guide (Bacon, 1989) for part of an earlier IAVCEI trip to the southern Cascade Range. The guide to Newberry Volcano describes the stops included in the 2017 field trip. Crater Lake and Newberry are the two best-preserved and most recent calderas in the Cascades Volcanic Arc. Although located in different settings in the arc, with Crater Lake on the arc axis and Newberry in the rear-arc, both volcanoes are located at the intersection of the arc and the northwest corner region of the extensional Basin and Range Province.

Cascades/Aleutian Play Fairway Analysis: Data and Map Files

DOE Data Explorer

Lisa Shevenell

2015-11-15

Contains Excel data files used to quantifiably rank the geothermal potential of each of the young volcanic centers of the Cascade and Aleutian Arcs using world power production volcanic centers as benchmarks. Also contains shapefiles used in play fairway analysis with power plant, volcano, geochemistry and structural data.

Integration Of Low-Cost Single-Frequency GPS Stations Using 'Spider' Technology Within Existing Dual-Frequency GPS Network at Soufrière Hills Volcano, Montserrat (West Indies): Processing And Results

NASA Astrophysics Data System (ADS)

Pascal, K.; Palamartchouk, K.; Lahusen, R. G.; Young, K.; Voight, B.

2015-12-01

Twenty years ago, began the eruption of the explosive Soufrière Hills Volcano, dominating the southern part of the island of Montserrat, West Indies. Five phases of effusive activity have now occurred, characterized by dome building and collapse, causing numerous evacuations and the emigration of half of the population. Over the years, the volcano monitoring network has greatly expanded. The GPS network, started from few geodetic markers, now consists of 14 continuous dual frequency GPS stations, distributed on and around the edifice, where topography and vegetation allow. The continuous GPS time series have given invaluable insight into the volcano behavior, notably revealing deflation/inflation cycles corresponding to phases and pauses of effusive activity, respectively. In 2014, collaboration of the CALIPSO Project (Penn State; NSF) with the Montserrat Volcano Observatory enriched the GPS and seismic monitoring networks with six 'spider' stations. The 'spiders', developed by R. Lahusen at Cascades Volcano Observatory, are designed to be deployed easily in rough areas and combine a low cost seismic station and a L1-only GPS station. To date, three 'spiders' have been deployed on Soufrière Hills Volcano, the closest at ~1 km from the volcanic conduit, adjacent to a lava lobe on the dome. Here we present the details of GPS data processing in a network consisting of both dual and single frequency receivers ('spiders') using GAMIT/GLOBK software. Processing together single and dual frequency data allowed their representation in a common reference frame, and a meaningful geophysical interpretation of all the available data. We also present the 'spiders' time series along with the results from the rest of the network and examine if any significant deformation, correlating with other manifestations of volcanic activity, has been recorded by the 'spiders' since deployment. Our results demonstrate that low cost GNSS equipment can serve as valuable components in volcano deformation monitoring networks.

Digital Data for Volcano Hazards in the Mount Jefferson Region, Oregon

USGS Publications Warehouse

Schilling, S.P.; Doelger, S.; Walder, J.S.; Gardner, C.A.; Conrey, R.M.; Fisher, B.J.

2008-01-01

Mount Jefferson has erupted repeatedly for hundreds of thousands of years, with its last eruptive episode during the last major glaciation which culminated about 15,000 years ago. Geologic evidence shows that Mount Jefferson is capable of large explosive eruptions. The largest such eruption occurred between 35,000 and 100,000 years ago. If Mount Jefferson erupts again, areas close to the eruptive vent will be severely affected, and even areas tens of kilometers (tens of miles) downstream along river valleys or hundreds of kilometers (hundreds of miles) downwind may be at risk. Numerous small volcanoes occupy the area between Mount Jefferson and Mount Hood to the north, and between Mount Jefferson and the Three Sisters region to the south. These small volcanoes tend not to pose the far-reaching hazards associated with Mount Jefferson, but are nonetheless locally important. A concern at Mount Jefferson, but not at the smaller volcanoes, is the possibility that small-to-moderate sized landslides could occur even during periods of no volcanic activity. Such landslides may transform as they move into lahars (watery flows of rock, mud, and debris) that can inundate areas far downstream. The geographic information system (GIS) volcano hazard data layer used to produce the Mount Jefferson volcano hazard map in USGS Open-File Report 99-24 (Walder and others, 1999) is included in this data set. Both proximal and distal hazard zones were delineated by scientists at the Cascades Volcano Observatory and depict various volcano hazard areas around the mountain.

Thermal surveillance of volcanoes of the Cascade Range and Iceland utilizing ERTS DCP systems and imagery

NASA Technical Reports Server (NTRS)

Friedman, J. D. (Principal Investigator)

1973-01-01

The author has identified the following significant results. Significant results of the thermal surveillance of volcanoes experiment during 1972 included the design, construction, emplacement, and successful operation at volcanic sites in the Cascade Range, North America and on Surtsey, Iceland, of automated thermistor arrays which transmit ground and fumarole temperatures via the ERTS-1 data communication system to Goddard Space Flight Center. Temperature, radiance, and anomalous heat flow variations are being plotted by a U.S. Geological Survey IBM 360/65 computer program to show daily fluctuations at each of the sites. Results are being compiled in conjunction with NASA and USGS aircraft infrared survey data to provide thermal energy yield estimates during the current repose period of several Cascade Range volcanic systems. ERTS-1 MSS images have provided new information on the extent of structural elements controlling thermal emission at Lassen Volcanic National Park.

Thermal surveillance of active volcanoes. [infrared scanner recordings of thermal anomalies of Mt. Baker volcano

NASA Technical Reports Server (NTRS)

Friedman, J. D. (Principal Investigator)

1974-01-01

The author has identified the following significant results. By the end of 1973, aerial infrared scanner traverses for thermal anomaly recordings of all Cascade Range volcanoes were essentially completed. Amplitude level slices of the Mount Baker anomalies were completed and compiled at a scale of 1:24,000, thus producing, for the first time, an accurate map of the distribution and intensity of thermal activity on Mount Baker. The major thermal activity is concentrated within the crater south of the main summit and although it is characterized by intensive solfataric activity and warm ground, it is largely subglacial, causing the development of sizable glacier perforation features. The outgoing radiative flux from the east breach anomalies is sufficient to account for the volume of ice melted to form the glacier perforations. DCP station 6251 has been monitoring a thermally anomalous area on the north slope of Mount Baker. The present thermal activity of Mount Baker accounts for continuing hydrothermal alteration in the crater south of the main summit and recurrent debris avalanches from Sherman Peak on its south rim. The infrared anomalies mapped as part of the experiment SR 251 are considered the basic evidence of the subglacial heating which was the probable triggering mechanism of an avalanche down Boulder Glacier on August 20-21, 1973.

Applications of geophysical methods to volcano monitoring

USGS Publications Warehouse

Wynn, Jeff; Dzurisin, Daniel; Finn, Carol A.; Kauahikaua, James P.; Lahusen, Richard G.

2006-01-01

The array of geophysical technologies used in volcano hazards studies - some developed originally only for volcano monitoring - ranges from satellite remote sensing including InSAR to leveling and EDM surveys, campaign and telemetered GPS networks, electronic tiltmeters and strainmeters, airborne magnetic and electromagnetic surveys, short-period and broadband seismic monitoring, even microphones tuned for infrasound. They include virtually every method used in resource exploration except large-scale seismic reflection. By “geophysical ” we include both active and passive methods as well as geodetic technologies. Volcano monitoring incorporates telemetry to handle high-bandwith cameras and broadband seismometers. Critical geophysical targets include the flux of magma in shallow reservoir and lava-tube systems, changes in active hydrothermal systems, volcanic edifice stability, and lahars. Since the eruption of Mount St. Helens in Washington State in 1980, and the eruption at Pu’u O’o in Hawai’i beginning in 1983 and still continuing, dramatic advances have occurred in monitoring technology such as “crisis GIS” and lahar modeling, InSAR interferograms, as well as gas emission geochemistry sampling, and hazards mapping and eruption predictions. The on-going eruption of Mount St. Helens has led to new monitoring technologies, including advances in broadband Wi-Fi and satellite telemetry as well as new instrumentation. Assessment of the gap between adequate monitoring and threat at the 169 potentially dangerous Holocene volcanoes shows where populations are dangerously exposed to volcanic catastrophes in the United States and its territories . This paper focuses primarily on Hawai’ian volcanoes and the northern Pacific and Cascades volcanoes. The US Geological Survey, the US National Park System, and the University of Utah cooperate in a program to monitor the huge Yellowstone volcanic system, and a separate observatory monitors the restive Long Valley caldera in collaboration with the US Forest Service. 

Quaternary extrusion rates of the Cascade Range, northwestern United States and southern British Columbia

NASA Astrophysics Data System (ADS)

Sherrod, David R.; Smith, James G.

1990-11-01

Quaternary (2-0 Ma) extrusion rates change significantly along the Cascade Range volcanic arc. The extrusion rate north of Mount Rainier is about 0.21 km3 km-1 m.y.-1; the rate in southern Washington and northern Oregon south to Mount Hood is about 1.6 km3 km-1 m.y.-1; in central Oregon the rate is 3-6 km3 km-1 m.y.-1; and in northern California, the rate is 3.2 km3 km-1 m.y.-1. Eruption style also changes along the arc but at latitudes different from rate changes. At the ends of the arc, volcanism is focused at isolated intermediate to silicic composite volcanoes. The composite volcanoes represent ˜30% of the total volume of the arc. Mafic volcanic fields partly ring some composite volcanoes, especially in the south. In contrast, volcanism is diffused in the middle of the arc, where numerous overlapping mafic shields and a few composite volcanoes have built a broad ridge. Contrasting eruption style may signify diffuse versus focused heat sources or may reflect changes in permeability to ascending magma along the arc.

The Southern Washington Cascades magmatic system imaged with magnetotellurics

NASA Astrophysics Data System (ADS)

Bowles-martinez, E.; Bedrosian, P.; Schultz, A.; Hill, G. J.; Peacock, J.

2016-12-01

The goal of the interdisciplinary iMUSH project (Imaging Magma Under Saint Helens) is to image the magmatic system of Mount Saint Helens (MSH), and to determine the relationship of this system to the greater Cascades volcanic arc. We are especially interested in an anomalously conductive crustal zone between MSH and Mount Adams known as the Southern Washington Cascades Conductor (SWCC), which early studies interpreted as accreted sediments, but more recently has been interpreted as a broad region of partial melt. MSH is located 50 km west of the main arc and is the most active of the Cascade volcanoes. Its 1980 eruption highlighted the need to understand this potentially hazardous volcanic system. We use wideband magnetotelluric (MT) data collected in 2014-2015 along with data from earlier studies to create a 3D model of the electrical resistivity throughout the region, covering MSH as well as Mount Adams and Mount Rainier along the main volcanic arc. We look at not only the volcanoes themselves, but also their relationship to one another and to regional geologic structures. Preliminary modeling identifies several conductive features, including a mid-crustal conductive region between MSH and Mount Adams that passes below Indian Heaven Volcanic Field and coincides with a region with a high Vp/Vs ratio identified in the seismic component of iMUSH. This suggests that it could be magmatic, but does not preclude the possibility of conductive sediments. Synthesis of seismic and MT data to address this question is ongoing. We also note a conductive zone running north-south just west of MSH that is likely associated with fluids within faults of the Saint Helens Seismic Zone. We finally note that curvature of the conductive lineament that defines the main Cascade arc suggests that the boundary of magmatism is influenced by compression within the Yakima Fold and Thrust Belt, east and southeast of Mount Adams.

Mantle and Crustal Sources of Carbon, Nitrogen, and Noble gases in Cascade-Range and Aleutian-Arc Volcanic gases

USGS Publications Warehouse

Symonds, Robert B.; Poreda, Robert J.; Evans, William C.; Janik, Cathy J.; Ritchie, Beatrice E.

2003-01-01

Here we report anhydrous chemical (CO2, H2S, N2, H2, CH4, O2, Ar, He, Ne) and isotopic (3He/4He, 40Ar/36Ar, δ13C of CO2, δ13C of CH4, δ15N) compositions of virtually airfree gas samples collected between 1994 and 1998 from 12 quiescent but potentially restless volcanoes in the Cascade Range and Aleutian Arc (CRAA). Sample sites include ≤173°C fumaroles and springs at Mount Shasta, Mount Hood, Mount St. Helens, Mount Rainier, Mount Baker, Augustine Volcano, Mount Griggs, Trident, Mount Mageik, Aniakchak Crater, Akutan, and Makushin. The chemical and isotopic data generally point to magmatic (CO2, Ar, He), shallow crustal sedimentary (hereafter, SCS) (CO2, N2, CH4), crustal (He), and meteoric (N2, Ar) sources of volatiles. CH4 clearly comes from SCS rocks in the subvolcanic systems because CH4 cannot survive the higher temperatures of deeper potential sources. Further evidence for a SCS source for CH4 as well as for non-mantle CO2 and non-meteoric N2 comes from isotopic data that show wide variations between volcanoes that are spatially very close and similar isotopic signatures from volcanoes from very disparate areas. Our results are in direct opposition to many recent studies on other volcanic arcs (Kita and others, 1993; Sano and Marty, 1995; Fischer and others, 1998), in that they point to a dearth of subducted components of CO2 and N2 in the CRAA discharges. Either the CRAA volcanoes are fundamentally different from volcanoes in other arcs or we need to reevaluate the significance of subducted C and N recycling in convergent-plate volcanoes.

Geothermal segmentation of the Cascade Range in the USA

USGS Publications Warehouse

Guffanti, Marianne; Muffler, L.J.; Mariner, R.H.; Sherrod, D.R.; Smith, James G.; Blackwell, D.D.; Weaver, C.S.

1990-01-01

Characteristics of the crustal thermal regime of the Quaternary Cascades vary systematically along the range. Spatially congruent changes in volcanic vent distribution, volcanic extrusion rate, hydrothermal discharge rate, and regional conductive heat flow define 5 geothermal segments. These segments are, from north to south: (1) the Washington Cascades north of Mount Rainier, (2) the Cascades from Mount Rainier to Mount Hood, (3) the Oregon Cascades from south of Mount Hood to the California border, (4) northernmost California, including Mount Shasta and Medicine Lake volcano, and (5) the Lassen region of northern California. This segmentation indicates that geothermal resource potential is not uniform in the Cascade Range. Potential varies from high in parts of Oregon to low in Washington north of Mount Rainier.

Languages of volcanic landscapes

Treesearch

Frederick J. Swanson

2008-01-01

As a young geologist in 1980, I felt a powerful attraction to volcanoes, and I thought I knew volcanoes rather well. I had studied volcanology. I had climbed volcanic peaks in the Cascades. And I had tried to be an attentive citizen of my volcanic region, the Pacific Northwest. But when I had a chance to go with other scientists to Mount St. Helens within days of its...

Catastrophic debris flows transformed from landslides in volcanic terrains : mobility, hazard assessment and mitigation strategies

USGS Publications Warehouse

Scott, Kevin M.; Macias, Jose Luis; Naranjo, Jose Antonio; Rodriguez, Sergio; McGeehin, John P.

2001-01-01

Communities in lowlands near volcanoes are vulnerable to significant volcanic flow hazards in addition to those associated directly with eruptions. The largest such risk is from debris flows beginning as volcanic landslides, with the potential to travel over 100 kilometers. Stratovolcanic edifices commonly are hydrothermal aquifers composed of unstable, altered rock forming steep slopes at high altitudes, and the terrain surrounding them is commonly mantled by readily mobilized, weathered airfall and ashflow deposits. We propose that volcano hazard assessments integrate the potential for unanticipated debris flows with, at active volcanoes, the greater but more predictable potential of magmatically triggered flows. This proposal reinforces the already powerful arguments for minimizing populations in potential flow pathways below both active and selected inactive volcanoes. It also addresses the potential for volcano flank collapse to occur with instability early in a magmatic episode, as well as the 'false-alarm problem'-the difficulty in evacuating the potential paths of these large mobile flows. Debris flows that transform from volcanic landslides, characterized by cohesive (muddy) deposits, create risk comparable to that of their syneruptive counterparts of snow and ice-melt origin, which yield noncohesive (granular) deposits, because: (1) Volcano collapses and the failures of airfall- and ashflow-mantled slopes commonly yield highly mobile debris flows as well as debris avalanches with limited runout potential. Runout potential of debris flows may increase several fold as their volumes enlarge beyond volcanoes through bulking (entrainment) of sediment. Through this mechanism, the runouts of even relatively small collapses at Cascade Range volcanoes, in the range of 0.1 to 0.2 cubic kilometers, can extend to populated lowlands. (2) Collapse is caused by a variety of triggers: tectonic and volcanic earthquakes, gravitational failure, hydrovolcanism, and precipitation, as well as magmatic activity and eruptions. (3) Risk of collapse begins with initial magmatic activity and increases as intrusion proceeds. An archetypal debris flow from volcanic terrain occurred in Colombia with a tectonic earthquake (M 6.4) in 1994. The Rio Piez conveyed a catastrophic wave of debris flow over 100 kilometers, coalesced from multiple slides of surflcial material weakened both by weathering and by hydrothermal alteration in a large strato- volcano. Similar seismogenic flows occurred in Mexico in 1920 (M -6.5), Chile in 1960 (M 9.2), and Ecuador in 1987 (M 6.1 and 6.9). Velocities of wave fronts in two examples were 60 to 90 km/hr (17-25 meters per second) over the initial 30 kilometers. Volcano flank and sector collapses may produce untransformed debris avalanches, as occurred initially at Mount St. Helens in 1980. However, at least as common is direct transformation of the failed mass to a debris flow. At two other volcanoes in the Cascade Range-- Mount Rainier and Mount Baker--rapid transformation and high mobility were typical of most of at least 15 Holocene flows. This danger exists downstream from many stratovolcanoes worldwide; the population at risk is near 150,000 and increasing at Mount Rainier. The first step in preventing future catastrophes is documenting past flows. Deposits of some debris flows, however, can be mistaken for those of less-mobile debris avalanches on the basis of mounds formed by buoyed megaclasts. Megaclasts may record only the proximal phase of a debris flow that began as a debris avalanche. Runout may have extended much farther, and thus furore flow mobility may be underestimated. Processes and behaviors of megaclast-bearing paleoflows are best inferred from the intermegaclast matrix. Mitigation strategy can respond to volcanic flows regardless of type and trigger by: (1) Avoidance: Limit settlement in flow pathways to numbers that can be evacuated after event warnings (flow is occurring). (2) Instrumental even

Sutter Buttes-the lone volcano in California's Great Valley

USGS Publications Warehouse

Hausback, Brain P.; Muffler, L.J. Patrick; Clynne, Michael A.

2011-01-01

The volcanic spires of the Sutter Buttes tower 2,000 feet above the farms and fields of California's Great Valley, just 50 miles north-northwest of Sacramento and 11 miles northwest of Yuba City. The only volcano within the valley, the Buttes consist of a central core of volcanic domes surrounded by a large apron of fragmental volcanic debris. Eruptions at the Sutter Buttes occurred in early Pleistocene time, 1.6 to 1.4 million years ago. The Sutter Buttes are not part of the Cascade Range of volcanoes to the north, but instead are related to the volcanoes in the Coast Ranges to the west in the vicinity of Clear Lake, Napa Valley, and Sonoma Valley.

Global Assessment of Volcanic Debris Hazards from Space

NASA Technical Reports Server (NTRS)

Watters, Robert J.

2003-01-01

Hazard (slope stability) assessment for different sectors of volcano edifices was successfully obtained from volcanoes in North and South America. The assessment entailed Hyperion images to locate portions of the volcano that were hydrothermally altered to clay rich rocks with zones that were also rich in alunite and other minerals. The identified altered rock zones were field checked and sampled. The rock strength of these zones was calculated from the field and laboratory measurements. Volcano modeling utilizing the distinct element method and limit equilibrium technique, with the calculated strength data was used to assess stability and deformation of the edifice. Modeling results give indications of possible failure volumes, velocities and direction. The models show the crucial role hydrothermally weak rock plays in reducing the strength o the volcano edifice and the rapid identification of weak rock through remote sensing techniques. Volcanoes were assessed in the Cascade Range (USA), Mexico, and Chile (ongoing).

Multi-year high-frequency hydrothermal monitoring of selected high-threat Cascade Range volcanoes

NASA Astrophysics Data System (ADS)

Crankshaw, I. M.; Archfield, S. A.; Newman, A. C.; Bergfeld, D.; Clor, L. E.; Spicer, K. R.; Kelly, P. J.; Evans, W. C.; Ingebritsen, S. E.

2018-05-01

From 2009 to 2015 the U.S. Geological Survey (USGS) systematically monitored hydrothermal behavior at selected Cascade Range volcanoes in order to define baseline hydrothermal and geochemical conditions. Gas and water data were collected regularly at 25 sites on 10 of the highest-risk volcanoes in the Cascade Range. These sites include near-summit fumarole groups and springs/streams that show clear evidence of magmatic influence (high 3He/4He ratios and/or large fluxes of magmatic CO2 or heat). Site records consist mainly of hourly temperature and hydrothermal-flux data. Having established baseline conditions during a multiyear quiescent period, the USGS reduced monitoring frequency from 2015 to present. The archived monitoring data are housed at (doi:10.5066/F72N5088). These data (1) are suitable for retrospective comparison with other continuous geophysical monitoring data and (2) will provide context during future episodes of volcanic unrest, such that unrest-related variations at these thoroughly characterized sites will be more clearly recognizable. Relatively high-frequency year-round data are essential to achieve these objectives, because many of the time series reveal significant diurnal, seasonal, and inter-annual variability that would tend to mask unrest signals in the absence of baseline data. Here we characterize normal variability for each site, suggest strategies to detect future volcanic unrest, and explore deviations from background associated with recent unrest.

Volcano-Monitoring Instrumentation in the United States, 2008

USGS Publications Warehouse

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

2010-01-01

The United States is one of the most volcanically active countries in the world. According to the global volcanism database of the Smithsonian Institution, the United States (including its Commonwealth of the Northern Mariana Islands) is home to about 170 volcanoes that are in an eruptive phase, have erupted in historical time, or have not erupted recently but are young enough (eruptions within the past 10,000 years) to be capable of reawakening. From 1980 through 2008, 30 of these volcanoes erupted, several repeatedly. Volcano monitoring in the United States is carried out by the U.S. Geological Survey (USGS) Volcano Hazards Program, which operates a system of five volcano observatories-Alaska Volcano Observatory (AVO), Cascades Volcano Observatory (CVO), Hawaiian Volcano Observatory (HVO), Long Valley Observatory (LVO), and Yellowstone Volcano Observatory (YVO). The observatories issue public alerts about conditions and hazards at U.S. volcanoes in support of the USGS mandate under P.L. 93-288 (Stafford Act) to provide timely warnings of potential volcanic disasters to the affected populace and civil authorities. To make efficient use of the Nation's scientific resources, the volcano observatories operate in partnership with universities and other governmental agencies through various formal agreements. The Consortium of U.S. Volcano Observatories (CUSVO) was established in 2001 to promote scientific cooperation among the Federal, academic, and State agencies involved in observatory operations. Other groups also contribute to volcano monitoring by sponsoring long-term installation of geophysical instruments at some volcanoes for specific research projects. This report describes a database of information about permanently installed ground-based instruments used by the U.S. volcano observatories to monitor volcanic activity (unrest and eruptions). The purposes of this Volcano-Monitoring Instrumentation Database (VMID) are to (1) document the Nation's existing, ground-based, volcano-monitoring capabilities, (2) answer queries within a geospatial framework about the nature of the instrumentation, and (3) provide a benchmark for planning future monitoring improvements. The VMID is not an archive of the data collected by monitoring instruments, nor is it intended to keep track of whether a station is temporarily unavailable due to telemetry or equipment problems. Instead, it is a compilation of basic information about each instrument such as location, type, and sponsoring agency. Typically, instruments installed expressly for volcano monitoring are emplaced within about 20 kilometers (km) of a volcanic center; however, some more distant instruments (as far away as 100 km) can be used under certain circumstances and therefore are included in the database. Not included is information about satellite-based and airborne sensors and temporarily deployed instrument arrays, which also are used for volcano monitoring but do not lend themselves to inclusion in a geospatially organized compilation of sensor networks. This Open-File Report is provided in two parts: (1) an Excel spreadsheet (http://pubs.usgs.gov/of/2009/1165/) containing the version of the Volcano-Monitoring Instrumentation Database current through 31 December 2008 and (2) this text (in Adobe PDF format), which serves as metadata for the VMID. The disclaimer for the VMID is in appendix 1 of the text. Updated versions of the VMID will be posted on the Web sites of the Consortium of U.S. Volcano Observatories (http://www.cusvo.org/) and the USGS Volcano Hazards Program http://volcanoes.usgs.gov/activity/data/index.php.

Crustal subsidence, seismicity, and structure near Medicine Lake Volcano, California

USGS Publications Warehouse

Dzurisin, D.; Donnelly-Nolan, J. M.; Evans, J.R.; Walter, S.R.

1991-01-01

The pattern of historical ground deformation, seismicity, and crustal structure near Medicine Lake volcano illustrates a close relation between magmatism and tectonism near the margin of the Cascade volcanic chain and the Basin and Range tectonic province. Subsidence occurs mainly by aseismic creep within 25km of the summit, where the crust has been heated and weakened by intrusions, and by normal faulting during episodic earthquake swarms in surrounding, cooler terrain. -from Authors

A field guide to Newberry Volcano, Oregon

USGS Publications Warehouse

Jenson, Robert A.; Donnelly-Nolan, Julie M.; McKay, Daniele

2009-01-01

Newberry Volcano is located in central Oregon at the intersection of the Cascade Range and the High Lava Plains. Its lavas range in age from ca. 0.5 Ma to late Holocene. Erupted products range in composition from basalt through rhyolite and cover ~3000 km2. The most recent caldera-forming eruption occurred ~80,000 years ago. This trip will highlight a revised understanding of the volcano's history based on new detailed geologic work. Stops will also focus on evidence for ice and flooding on the volcano, as well as new studies of Holocene mafic eruptions. Newberry is one of the most accessible U.S. volcanoes, and this trip will visit a range of lava types and compositions including tholeiitic and calc-alkaline basalt flows, cinder cones, and rhyolitic domes and tuffs. Stops will include early distal basalts as well as the youngest intracaldera obsidian flow.

Seismic evidence for a possible deep crustal hot zone beneath Southwest Washington.

PubMed

Flinders, Ashton F; Shen, Yang

2017-08-07

Crustal pathways connecting deep sources of melt and the active volcanoes they supply are poorly understood. Beneath Mounts St. Helens, Adams, and Rainier these pathways connect subduction-induced ascending melts to shallow magma reservoirs. Petrogenetic modeling predicts that when these melts are emplaced as a succession of sills into the lower crust they generate deep crustal hot zones. While these zones are increasingly recognized as a primary site for silicic differentiation at a range of volcanic settings globally, imaging them remains challenging. Near Mount Rainier, ascending melt has previously been imaged ~28 km northwest of the volcano, while to the south, the volcano lies on the margin of a broad conductive region in the deep crust. Using 3D full-waveform tomography, we reveal an expansive low-velocity zone, which we interpret as a possible hot zone, linking ascending melts and shallow reservoirs. This hot zone may supply evolved magmas to Mounts St. Helens and Adams, and possibly Rainier, and could contain approximately twice the melt volume as the total eruptive products of all three volcanoes combined. Hot zones like this may be the primary reservoirs for arc volcanism, influencing compositional variations and spatial-segmentation along the entire 1100 km-long Cascades Arc.

Seismic evidence for a possible deep crustal hot zone beneath Southwest Washington

USGS Publications Warehouse

Flinders, Ashton; Shen, Yang

2017-01-01

Crustal pathways connecting deep sources of melt and the active volcanoes they supply are poorly understood. Beneath Mounts St. Helens, Adams, and Rainier these pathways connect subduction-induced ascending melts to shallow magma reservoirs. Petrogenetic modeling predicts that when these melts are emplaced as a succession of sills into the lower crust they generate deep crustal hot zones. While these zones are increasingly recognized as a primary site for silicic differentiation at a range of volcanic settings globally, imaging them remains challenging. Near Mount Rainier, ascending melt has previously been imaged ~28 km northwest of the volcano, while to the south, the volcano lies on the margin of a broad conductive region in the deep crust. Using 3D full-waveform tomography, we reveal an expansive low-velocity zone, which we interpret as a possible hot zone, linking ascending melts and shallow reservoirs. This hot zone may supply evolved magmas to Mounts St. Helens and Adams, and possibly Rainier, and could contain approximately twice the melt volume as the total eruptive products of all three volcanoes combined. Hot zones like this may be the primary reservoirs for arc volcanism, influencing compositional variations and spatial-segmentation along the entire 1100 km-long Cascades Arc.

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

USGS Publications Warehouse

Fink, Jonathan H.; Anderson, Steven W.

2017-07-19

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

Post-11,000-year volcanism at Medicine Lake Volcano, Cascade Range, northern California

USGS Publications Warehouse

Donnelly-Nolan, J. M.; Champion, D.E.; Miller, C.D.; Grove, T.L.; Trimble, D.A.

1990-01-01

Eruptive activity during the past 11,000 years at Medicine Lake volcano has been episodic. Eight eruptions produced about 5.3 km3 of basaltic lava during an interval of a few hundred years about 10 500 years B.P. After a hiatus of about 6000 years, eruptive activity resumed with a small andesite eruption at about 4300 years B.P. Approximately 2.5 km3 of lava with compositions ranging from basalt to rhyolite vented in nine eruptions during an interval of about 3400 years in late Holocene time. The most recent eruption occurred about 900 years B.P. A compositional gap in SiO2 values of erupted lavas occurs between 58 and 63%. The gap is spanned by chilled magmatic inclusions in late Holocene silicic lavas. Late Holocene andesitic to rhyolitic lavas were probably derived by fractionation, assimilation, and mixing from high-alumina basalt parental magma, possibly from basalt intruded into the volcano during the early mafic episode. Eruptive activity is probably driven by intrusions of basalt that occur during E-W stretching of the crust in an extensional tectonic environment. Vents are typically aligned parallel or subparallel to major structural features, most commonly within 30?? of north. Intruded magma should provide adequate heat for commercial geothermal development if sufficient fluids can be found. -from Authors

Field-trip guides to selected volcanoes and volcanic landscapes of the western United States

USGS Publications Warehouse

,

2017-06-23

The North American Cordillera is home to a greater diversity of volcanic provinces than any comparably sized region in the world. The interplay between changing plate-margin interactions, tectonic complexity, intra-crustal magma differentiation, and mantle melting have resulted in a wealth of volcanic landscapes.  Field trips in this guide book collection (published as USGS Scientific Investigations Report 2017–5022) visit many of these landscapes, including (1) active subduction-related arc volcanoes in the Cascade Range; (2) flood basalts of the Columbia Plateau; (3) bimodal volcanism of the Snake River Plain-Yellowstone volcanic system; (4) some of the world’s largest known ignimbrites from southern Utah, central Colorado, and northern Nevada; (5) extension-related volcanism in the Rio Grande Rift and Basin and Range Province; and (6) the eastern Sierra Nevada featuring Long Valley Caldera and the iconic Bishop Tuff.  Some of the field trips focus on volcanic eruptive and emplacement processes, calling attention to the fact that the western United States provides opportunities to examine a wide range of volcanological phenomena at many scales.The 2017 Scientific Assembly of the International Association of Volcanology and Chemistry of the Earth’s Interior (IAVCEI) in Portland, Oregon, was the impetus to update field guides for many of the volcanoes in the Cascades Arc, as well as publish new guides for numerous volcanic provinces and features of the North American Cordillera. This collection of guidebooks summarizes decades of advances in understanding of magmatic and tectonic processes of volcanic western North America. These field guides are intended for future generations of scientists and the general public as introductions to these fascinating areas; the hope is that the general public will be enticed toward further exploration and that scientists will pursue further field-based research.

Validation of Innovative Exploration Technologies for Newberry Volcano: Drill Site Location Map 2010

DOE Data Explorer

Jaffe, Todd

2012-01-01

Newberry seeks to explore "blind" (no surface evidence) convective hydrothermal systems associated with a young silicic pluton on the flanks of Newberry Volcano. This project will employ a combination of innovative and conventional techniques to identify the location of subsurface geothermal fluids associated with the hot pluton. Newberry project drill site location map 2010. Once the exploration mythology is validated, it can be applied throughout the Cascade Range and elsewhere to locate and develop “blind” geothermal resources.

A Numerical Program for Steady-State Flow of Magma-Gas Mixtures Through Vertical Eruptive Conduits

DTIC Science & Technology

2000-01-01

1997, Evidence for water influx from a caldera lake during the explosive hydromagmatic eruption of 1790, Kilauea Volcano , Hawaii : Journal of...method: Journal of Geology, v. 94, p. 626-630. Head, J.W.I., and Wilson, L., 1987, Lava fountain heights at Pu’u ’O’o, Kilauea , Hawaii : Indicators of...Additional information can be obtained from Copies of this report can be purchased from: U.S. Geological Survey U.S. Geological Survey Cascades Volcano

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reidel, Steve P.

The Three Sisters volcanoes in the central Oregon Cascade Range are in the news again. Near the end of March there were about 100 small earthquakes that occurred 3 miles west of South Sister. The US Geological Survey attributed the earthquakes to a ''modest amount of magma'' accumulating at a depth of about 4 miles. The magma also has caused about 10 inches of uplift there since 1997. Geologists are now trying to determine what this really means to the area. Are we seeing the beginning phase of a future eruption or is it simply just a normal event inmore » the life of a young volcano? This is a newspaper article about the Three Sisters volcanoes« less

Quaternary Magmatism in the Cascades - Geologic Perspectives

USGS Publications Warehouse

Hildreth, Wes

2007-01-01

Foreward The Cascade magmatic arc is a belt of Quaternary volcanoes that extends 1,250 km from Lassen Peak in northern California to Meager Mountain in Canada, above the subduction zone where the Juan de Fuca Plate plunges beneath the North American Plate. This Professional Paper presents a synthesis of the entire volcanic arc, addressing all 2,300 known Quaternary volcanoes, not just the 30 or so visually prominent peaks that comprise the volcanic skyline. Study of Cascade volcanoes goes back to the geological explorers of the late 19th century and the seminal investigations of Howel Williams in the 1920s and 1930s. However, major progress and application of modern scientific methods and instrumentation began only in the 1970s with the advent of systematic geological, geophysical, and geochemical studies of the entire arc. Initial stimulus from the USGS Geothermal Research Program was enhanced by the USGS Volcano Hazards Program following the 1980 eruption of Mount St. Helens. Together, these two USGS Programs have provided more than three decades of stable funding, staffing, and analytical support. This Professional Paper summarizes the resultant USGS data sets and integrates them with the parallel contributions of other investigators. The product is based upon an all-encompassing and definitive geological database, including chemical and isotopic analyses to characterize the rocks and geochronology to provide the critical time constraints. Until now, this massive amount of data has not been summarized, and a systematic and uniform interpretation firmly grounded in geological fact has been lacking. Herein lies the primary utility of this Cascade volume. It not only will be the mandatory starting point for new workers, but also will provide essential geological context to broaden the perspectives of current investigators of specific Cascade volcanoes. Wes Hildreth's insightful understanding of volcanic processes and his uncompromising scientific integrity make him uniquely qualified to present this synthesis. During more than three decades of volcanological studies, he has carried out comprehensive investigations of Mount Adams, Mount Baker, the Three Sisters, and the Simcoe Mountains Volcanic Field. He also brings a broad experience in other volcanic arcs, having conducted integrated field and laboratory investigations at several major volcanic centers in the Andes and the Aleutian arcs. His expertise and perspective have been further enhanced by in-depth petrologic studies of caldera environments, primarily in Long Valley, California, and Yellowstone. On the basis of all these field and laboratory investigations and exhaustive literature searches, he has published three definitive petrologic syntheses addressing the passage and transformation of basaltic magmas from their mantle sources through the crust to form the many types of volcanic manifestations at the Earth's surface. A major strength of this Professional Paper is that it adheres to data first and foremost, and only then correlates these data with relevant theories. Petrological and geophysical interpretation is left to the later sections of the volume, and even there is never allowed to stray from the pertinent databases. Hildreth's interpretations are not just idle speculations, but are carefully reasoned inferences firmly based on his thorough evaluation of the observational geological data. Professional Paper 1744 should not be skimmed lightly, in the hope that the salient points will quickly rub off. Instead, every section, indeed every paragraph, presents scholarly observations and insightful interpretations that demand careful and thoughtful study. This volume will influence and guide the course of Cascade investigations for decades to come.

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

USGS Publications Warehouse

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

2012-01-01

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

51F earth observations

NASA Image and Video Library

2009-06-25

51F-37-097 (29 July-6 Aug 1985) --- The snow capped peaks of the Oregon Cascades are clearly seen. From bottom to top we see Mount Hood, Mount Jefferson, and the Three Sisters volcanos. The Columbia River is at the bottom. The Deschutes River system and canyon, the scene of railroad wars nearly a century ago, is at the left side. The Cascades make a very distinct rain shadow between the moist forests to the right and the semiario lands to the east (left) of these great mountains.

Thermal surveillance of volcanoes

NASA Technical Reports Server (NTRS)

Friedman, J. D. (Principal Investigator)

1972-01-01

The author has identified the following significant results. A systematic aircraft program to monitor changes in the thermal emission from volcanoes of the Cascade Range has been initiated and is being carried out in conjunction with ERTS-1 thermal surveillance experiments. Night overflights by aircraft equipped with thermal infrared scanners sensitive to terrestrial emission in the 4-5.5 and 8-14 micron bands are currently being carried out at intervals of a few months. Preliminary results confirm that Mount Rainier, Mount Baker, Mount Saint Helens, Mount Shasta, and the Lassen area continue to be thermally active, although with the exception of Lassen which erupted between 1914 and 1917, and Mount Saint Helens which had a series of eruptions between 1831 and 1834, there has been no recent eruptive activity. Excellent quality infrared images recorded over Mount Rainier, as recently as April, 1972, show similar thermal patterns to those reported in 1964-1966. Infrared images of Mount Baker recorded in November 1970 and again in April 1972 revealed a distinct array of anomalies 1000 feet below the crater rim and associated with fumaroles or structures permitting convective heat transfer to the surface.

Glacier quakes mimicking volcanic earthquakes: The challenge of monitoring ice-clad volcanoes and some solutions

NASA Astrophysics Data System (ADS)

Allstadt, K.; Carmichael, J. D.; Malone, S. D.; Bodin, P.; Vidale, J. E.; Moran, S. C.

2012-12-01

Swarms of repeating earthquakes at volcanoes are often a sign of volcanic unrest. However, glaciers also can generate repeating seismic signals, so detecting unrest at glacier-covered volcanoes can be a challenge. We have found that multi-day swarms of shallow, low-frequency, repeating earthquakes occur regularly at Mount Rainier, a heavily glaciated stratovolcano in Washington, but that most swarms had escaped recognition until recently. Typically such earthquakes were too small to be routinely detected by the seismic network and were often buried in the noise on visual records, making the few swarms that had been detected seem more unusual and significant at the time they were identified. Our comprehensive search for repeating earthquakes through the past 10 years of continuous seismic data uncovered more than 30 distinct swarms of low-frequency earthquakes at Rainier, each consisting of hundreds to thousands of events. We found that these swarms locate high on the glacier-covered edifice, occur almost exclusively between late fall and early spring, and that their onset coincides with heavy snowfalls. We interpret the correlation with snowfall to indicate a seismically observable glacial response to snow loading. Efforts are underway to confirm this by monitoring glacier motion before and after a major snowfall event using ground based radar interferometry. Clearly, if the earthquakes in these swarms reflect a glacial source, then they are not directly related to volcanic activity. However, from an operational perspective they make volcano monitoring difficult because they closely resemble earthquakes that often precede and accompany volcanic eruptions. Because we now have a better sense of the background level of such swarms and know that their occurrence is seasonal and correlated with snowfall, it will now be easier to recognize if future swarms at Rainier are unusual and possibly related to volcanic activity. To methodically monitor for such unusual activity, we are implementing an automatic detection algorithm to continuously search for repeating earthquakes at Mount Rainier, an algorithm that we eventually intend to apply to other Cascade volcanoes. We propose that a comprehensive routine that characterizes background levels of repeating earthquakes and the degree of correlation with weather and seasonal forcing, combined with real-time monitoring for repeating earthquakes, will provide a means to more rapidly discriminate between glacier seismicity and seismicity related to volcanic activity on monitored glacier-clad volcanoes.

MATLAB tools for improved characterization and quantification of volcanic incandescence in Webcam imagery; applications at Kilauea Volcano, Hawai'i

USGS Publications Warehouse

Patrick, Matthew R.; Kauahikaua, James P.; Antolik, Loren

2010-01-01

Webcams are now standard tools for volcano monitoring and are used at observatories in Alaska, the Cascades, Kamchatka, Hawai'i, Italy, and Japan, among other locations. Webcam images allow invaluable documentation of activity and provide a powerful comparative tool for interpreting other monitoring datastreams, such as seismicity and deformation. Automated image processing can improve the time efficiency and rigor of Webcam image interpretation, and potentially extract more information on eruptive activity. For instance, Lovick and others (2008) provided a suite of processing tools that performed such tasks as noise reduction, eliminating uninteresting images from an image collection, and detecting incandescence, with an application to dome activity at Mount St. Helens during 2007. In this paper, we present two very simple automated approaches for improved characterization and quantification of volcanic incandescence in Webcam images at Kilauea Volcano, Hawai`i. The techniques are implemented in MATLAB (version 2009b, Copyright: The Mathworks, Inc.) to take advantage of the ease of matrix operations. Incandescence is a useful indictor of the location and extent of active lava flows and also a potentially powerful proxy for activity levels at open vents. We apply our techniques to a period covering both summit and east rift zone activity at Kilauea during 2008?2009 and compare the results to complementary datasets (seismicity, tilt) to demonstrate their integrative potential. A great strength of this study is the demonstrated success of these tools in an operational setting at the Hawaiian Volcano Observatory (HVO) over the course of more than a year. Although applied only to Webcam images here, the techniques could be applied to any type of sequential images, such as time-lapse photography. We expect that these tools are applicable to many other volcano monitoring scenarios, and the two MATLAB scripts, as they are implemented at HVO, are included in the appendixes. These scripts would require minor to moderate modifications for use elsewhere, primarily to customize directory navigation. If the user has some familiarity with MATLAB, or programming in general, these modifications should be easy. Although we originally anticipated needing the Image Processing Toolbox, the scripts in the appendixes do not require it. Thus, only the base installation of MATLAB is needed. Because fairly basic MATLAB functions are used, we expect that the script can be run successfully by versions earlier than 2009b.

Earth Observations taken by the Expedition 13 crew

NASA Image and Video Library

2006-07-19

ISS013-E-54243 (19 July 2006) --- Crater Lake, Oregon is featured in this image photographed by an Expedition 13 crewmember on the International Space Station. Crater Lake is formed from the caldera (collapsed magma chamber) of a former volcano known as Mount Mazama. Part of the Cascades volcanic chain, Mount Mazama is situated between the Three Sisters volcanoes to the north and Mount Shasta to the south. While considered a dormant volcano, Crater Lake is part of the United States Geological Survey Cascades Volcano Observatory seismic monitoring network. The dark blue water coloration is typical of the 592 meter (1943 feet) deep Crater Lake; light blue-green areas to the southeast of Wizard Island (along the southern crater rim) most probably correspond to particulates either on or just below the water surface. A light dusting of snow fills the summit cone of Wizard Island. Some of the older lava flows in the area are associated with Mount Scott to the east-southeast of the Lake. Water is lost only by evaporation and seepage, and is only replenished by rainwater and snowmelt from the surrounding crater walls. These processes help maintain minimal sediment input into the lake and exceptional water clarity. The Crater Lake ecosystem is of particular interest to ecologists because of its isolation from the regional landscape, and its overall pristine quality is important to recreational users of Crater Lake National Park (447,240 visitors in 2005). The United States National Park Service maintains programs to monitor changes (both natural and human impacts) to Crater Lake.

Springs, streams, and gas vent on and near Mount Adams volcano, Washington

USGS Publications Warehouse

Nathenson, Manuel; Mariner, Robert H.

2013-01-01

Springs and some streams on Mount Adams volcano have been sampled for chemistry and light stable isotopes of water. Spring temperatures are generally cooler than air temperatures from weather stations at the same elevation. Spring chemistry generally reflects weathering of volcanic rock from dissolved carbon dioxide. Water in some springs and streams has either dissolved hydrothermal minerals or has reacted with them to add sulfate to the water. Some samples appear to have obtained their sulfate from dissolution of gypsum while some probably involve reaction with sulfide minerals such as pyrite. Light stable isotope data for water from springs follow a local meteoric water line, and the variation of isotopes with elevation indicate that some springs have very local recharge and others have water from elevations a few hundred meters higher. No evidence was found for thermal or slightly thermal springs on Mount Adams. A sample from a seeping gas vent on Mount Adams was at ambient temperature, but the gas is similar to that found on other Cascade volcanoes. Helium isotopes are 4.4 times the value in air, indicating that there is a significant component of mantle helium. The lack of fumaroles on Mount Adams and the ambient temperature of the gas indicates that the gas is from a hydrothermal system that is no longer active.

Near-real-time information products for Mount St. Helens -- tracking the ongoing eruption: Chapter 3 in A volcano rekindled: the renewed eruption of Mount St. Helens, 2004-2006

USGS Publications Warehouse

Qamar, Anthony I.; Malone, Stephen; Moran, Seth C.; Steele, William P.; Thelen, Weston A.; Sherrod, David R.; Scott, William E.; Stauffer, Peter H.

2008-01-01

The rapid onset of energetic seismicity on September 23, 2004, at Mount St. Helens caused seismologists at the Pacific Northwest Seismic Network and the Cascades Volcano Observatory to quickly improve and develop techniques that summarized and displayed seismic parameters for use by scientists and the general public. Such techniques included webicorders (Web-based helicorder-like displays), graphs showing RSAM (real-time seismic amplitude measurements), RMS (root-mean-square) plots, spectrograms, location maps, automated seismic-event detectors, focal mechanism solutions, automated approximations of earthquake magnitudes, RSAM-based alarms, and time-depth plots for seismic events. Many of these visual-information products were made available publicly as Web pages generated and updated routinely. The graphs and maps included short written text that explained the concepts behind them, which increased their value to the nonseismologic community that was tracking the eruption. Laypeople could read online summaries of the scientific interpretations and, if they chose, review some of the basic data, thereby providing a better understanding of the data used by scientists to make interpretations about ongoing eruptive activity, as well as a better understanding of how scientists worked to monitor the volcano.

Mt. St. Helens

NASA Image and Video Library

2001-10-22

This 3-D anaglyph image of Mt. St. Helens volcano combines the nadir-looking and back-looking band 3 images of ASTER. To view the image in stereo, you will need blue-red glasses. Make sure to look through the red lens with your left eye. This ASTER image of Mt. St. Helens volcano in Washington was acquired on August 8, 2000 and covers an area of 37 by 51 km. Mount Saint Helens, a volcano in the Cascade Range of southwestern Washington that had been dormant since 1857, began to show signs of renewed activity in early 1980. On 18 May 1980, it erupted with such violence that the top of the mountain was blown off, spewing a cloud of ash and gases that rose to an altitude of 19 kilometers. The blast killed about 60 people and destroyed all life in an area of some 180 square kilometers (some 70 square miles), while a much larger area was covered with ash and debris. It continues to spit forth ash and steam intermittently. As a result of the eruption, the mountain's elevation decreased from 2,950 meters to 2,549 meters. The image is centered at 46.2 degrees north latitude, 122.2 degrees west longitude. http://photojournal.jpl.nasa.gov/catalog/PIA11160

Monitoring and modeling ice-rock avalanches from ice-capped volcanoes: A case study of frequent large avalanches on Iliamna Volcano, Alaska

USGS Publications Warehouse

Huggel, C.; Caplan-Auerbach, J.; Waythomas, C.F.; Wessels, R.L.

2007-01-01

Iliamna is an andesitic stratovolcano of the Aleutian arc with regular gas and steam emissions and mantled by several large glaciers. Iliamna Volcano exhibits an unusual combination of frequent and large ice-rock avalanches in the order of 1 ?? 106??m3 to 3 ?? 107??m3 with recent return periods of 2-4??years. We have reconstructed an avalanche event record for the past 45??years that indicates Iliamna avalanches occur at higher frequency at a given magnitude than other mass failures in volcanic and alpine environments. Iliamna Volcano is thus an ideal site to study such mass failures and its relation to volcanic activity. In this study, we present different methods that fit into a concept of (1) long-term monitoring, (2) early warning, and (3) event documentation and analysis of ice-rock avalanches on ice-capped active volcanoes. Long-term monitoring methods include seismic signal analysis, and space-and airborne observations. Landsat and ASTER satellite data was used to study the extent of hydrothermally altered rocks and surface thermal anomalies at the summit region of Iliamna. Subpixel heat source calculation for the summit regions where avalanches initiate yielded temperatures of 307 to 613??K assuming heat source areas of 1000 to 25??m2, respectively, indicating strong convective heat flux processes. Such heat flow causes ice melting conditions and is thus likely to reduce the strength at the base of the glacier. We furthermore demonstrate typical seismic records of Iliamna avalanches with rarely observed precursory signals up to two hours prior to failure, and show how such signals could be used for a multi-stage avalanche warning system in the future. For event analysis and documentation, space- and airborne observations and seismic records in combination with SRTM and ASTER derived terrain data allowed us to reconstruct avalanche dynamics and to identify remarkably similar failure and propagation mechanisms of Iliamna avalanches for the past 45??years. Simple avalanche flow modeling was able to reasonably replicate Iliamna avalanches and can thus be applied for hazard assessments. Hazards at Iliamna Volcano are low due to its remote location; however, we emphasize the transfer potential of the methods presented here to other ice-capped volcanoes with much higher hazards such as those in the Cascades or the Andes. ?? 2007 Elsevier B.V. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rose, T

I'm writing at the request of the Pit River Tribe to offer my professional opinion as a geochemist regarding the origin of groundwater discharge at the Fall River Springs, Shasta Co., California. In 1997, I conducted a study of the large volume cold springs associated with the Cascade Volcanoes in northern California, in collaboration with one of my colleagues. This work was published as a Lawrence Livermore National Laboratory report (Davisson and Rose, 1997). The Fall River Springs emerge from the distal end of the Giant Crater Lava Field, a laterally extensive basalt flow that stretches from the southern flankmore » of Medicine Lake Volcano southward for a distance of 40 km. Both Medicine Lake Volcano and the Giant Crater Lava Field have virtually no surface water drainages. Precipitation that falls in these areas is inferred to seep into fractures in the rock, where it is carried down gradient under the force of gravity. Mean annual precipitation rates on Medicine Lake Volcano and the Giant Crater Lava field are adequate to account for the {approx}1200 ft{sup 3}/sec discharge of the Fall River Springs. To evaluate the origin of the springs using geochemical methods, water samples were collected from the Fall River Springs and the Medicine Lake highlands and analyzed for oxygen and hydrogen isotope ratios. The isotope ratios measured for a groundwater sample are diagnostic of the average composition of the precipitation from which the water was derived. The isotope ratios of rain and snow also vary systematically with elevation, such that groundwater derived from recharge at higher elevations can be distinguished from that which originated at lower elevations. The stable isotope data for the Fall River Springs are consistent with groundwater recharge on the Medicine Lake Volcano and adjacent lava field. Mass balance calculations suggest that approximately half of the Fall River Springs flow is derived from the volcanic edifice. Rose and Davisson (1996) showed that the large volume cold springs associated with the Cascade Volcanoes commonly contain dissolved CO{sub 2} that originated from the volcanoes. This volcanic CO{sub 2} component is readily identified from carbon-14 measurements of the water. Carbon-14 analyses of the Fall River samples indicate that at least 27% of the dissolved inorganic carbon in the springs was derived from a volcanic CO{sub 2} source. Such a large volcanic CO{sub 2} flux requires that the groundwater supplying flow to the Fall River Springs must originate from a volcano where magma degassing is actively occurring. Given the hydrogeologic configuration of the Fall River aquifer system, it appears that the Medicine Lake Volcano is the only likely source of the volcanic CO{sub 2}. These data independently confirm the Medicine Lake highlands as a significant recharge source for the Fall River Springs. Moreover, these data indicate that groundwater recharge occurring on Medicine Lake Volcano must interact with a CO{sub 2} volatile phase derived from the geothermal system beneath the volcano. The lack of hot springs on Medicine Lake Volcano suggests that the geothermal system underlying the volcano is relatively tightly sealed. Nevertheless, it is probable that the geothermal fluid originates from precipitation falling on the volcanic edifice. This is the same water that supplies an important fraction of the Fall River Spring discharge. The source of the geothermal fluid can be evaluated using stable isotopes. The oxygen isotope signature of the geothermal fluid may have been modified by high temperature oxygen isotope exchange with the surrounding rock, but the hydrogen isotope signature should still be diagnostic of the origin of the fluid. Although the geothermal system appears to be largely decoupled from the shallow groundwater system that supplies the Fall River Springs, it is uncertain what impact the development of the geothermal system as an energy resource would have on groundwater circulation patterns on the volcano. Given the importance of the Fall River Springs as a water resource for the State of California, it would be prudent to carefully evaluate this question before proceeding with geothermal energy development on Medicine Lake Volcano.« less

Cascades Ecoregion: Chapter 11 in Status and trends of land change in the Western United States--1973 to 2000

USGS Publications Warehouse

Sorenson, Daniel G.

2012-01-01

The Cascades Ecoregion (Omernik, 1987; U.S. Environmental Protection Agency, 1997) covers approximately 46,787 km2 (18,064 mi2) in Washington, Oregon, and California (fig. 1). The main body of the ecoregion extends from Snoqualmie Pass, Washington, in the north, to Hayden Mountain, near State Highway 66 in southern Oregon. Also included in the ecoregion is a small isolated section south of Bend, Oregon, as well as a larger one around Mount Shasta, California. The ecoregion is bounded on the west by the Klamath Mountains, Willamette Valley, and Puget Lowland Ecoregions; on the north by the North Cascades Ecoregion; and on the east by the Eastern Cascades Slopes and Foothills Ecoregion. The Cascades Ecoregion is a forested, mountainous ecoregion, and it contains a large amount of Cenozoic volcanic rock and many active and inactive volcanoes, especially in the east (McNab and Avers, 1994). Elevations range from near sea level at the Columbia River to 4,390 m at Mount Rainier in Washington, with most of the ecoregion between 645 and 2,258 m. The west side of the ecoregion is characterized by long, steep ridges and wide river valleys. Subalpine meadows are present at higher elevations, and alpine glaciers have left till and outwash deposits (McNab and Avers, 1994). Precipitation in the Cascades Ecoregion ranges from 1,300 to 3,800 mm, falling mostly as rain and snow from October to June. Average annual temperatures range from –1ºC to 11ºC. The length of the growing season varies from less than 30 days to 240 days (McNab and Avers, 1994).

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

USGS Publications Warehouse

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 detected in a timely manner and, in the case of magnitude = 1 earthquakes, reliably located.

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

USGS Publications Warehouse

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

2017-08-17

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

Database for the geologic map of upper Eocene to Holocene volcanic and related rocks in the Cascade Range, Washington

USGS Publications Warehouse

Barron, Andrew D.; Ramsey, David W.; Smith, James G.

2014-01-01

This digital database contains information used to produce the geologic map published as Sheet 1 in U.S. Geological Survey Miscellaneous Investigations Series Map I-2005. (Sheet 2 of Map I-2005 shows sources of geologic data used in the compilation and is available separately). Sheet 1 of Map I-2005 shows the distribution and relations of volcanic and related rock units in the Cascade Range of Washington at a scale of 1:500,000. This digital release is produced from stable materials originally compiled at 1:250,000 scale that were used to publish Sheet 1. The database therefore contains more detailed geologic information than is portrayed on Sheet 1. This is most noticeable in the database as expanded polygons of surficial units and the presence of additional strands of concealed faults. No stable compilation materials exist for Sheet 1 at 1:500,000 scale. The main component of this digital release is a spatial database prepared using geographic information systems (GIS) applications. This release also contains links to files to view or print the map sheet, main report text, and accompanying mapping reference sheet from Map I-2005. For more information on volcanoes in the Cascade Range in Washington, Oregon, or California, please refer to the U.S. Geological Survey Volcano Hazards Program website.

Crystallization Conditions at Cascade and Other Arc Volcanoes: The Role of Recharge, and Ultimate, Proximal and Immediate Causes of Eruption

NASA Astrophysics Data System (ADS)

Putirka, K. D.

2016-12-01

A number of hypotheses have been offered to explain why volcanoes erupt. These include magma mixing, mafic recharge, or partial crystallization, any of which can drive parts or all of a system to vapor saturation, and so add to a magma's buoyancy. Age dates indicate long pre-eruption storage times for felsic magmas erupted at arcs, indicating that mafic recharge magmas, which can reinvigorate such systems, is a possible eruption trigger. However, plutonic systems reveal numerous recharge events that have no obvious ties to eruption (Coint et al. 2013; Putirka et al. 2014). And crystallization conditions at some arc systems support the implicit view, that recharge might be a necessary, but not a sufficient condition for eruption. At several Cascade volcanoes, Cpx and Amp crystals record coolings of 100-300oC. The Cpx grains derive exclusively from mafic enclaves, while Amp grains derive from both host and enclave materials. These considerable coolings call for a time lag following recharge, and indicate that vapor saturation is a proximal, although not necessarily an immediate cause of eruption. But we cannot discount recharge altogether. At the Cascades and at other arcs, Cpx crystalizes throughout the middle and upper crust, mostly from the surface down to 15 km. And high Fo olivine grains provide evidence for very hot magmas that intrude the upper mantle and lower crust, and possibly the middle crust, if hydrous. Volcanic pathways thus clearly extend into the middle crust, and at times, well below the Moho. It is unclear to what extent these deep pathways are hydraulically connected to the surface, or the role of deep-seated processes in initiating or sustaining eruptions. Progress in understanding these pathways, and triggering mechanisms, requires our differentiating "ultimate", "proximal" and "immediate" causes, and determining which of various magmatic processes provide necessary or sufficient conditions for eruption.

Short Magma Residence Times at Mt. Rainier and the Probable Absence of a Large, Integrated, and Long-lived Magma Reservoir System

NASA Astrophysics Data System (ADS)

Sisson, T. W.; Lanphere, M. A.

2003-12-01

Intensive, high-precision K-Ar and 40Ar/39Ar geochronology have proven essential for producing modern geologic maps of volcanoes and from these determining the volcanoes' time-volume histories. If sufficiently abundant, these data can also reveal aspects of the magma supply system. For Cascade volcanoes a general result has been the demonstration that edifice growth is highly episodic. Mount Rainier grew in the last 500,000 years atop the remains of an ancestral edifice that was active in the same location 1 - 2 Myr ago. The 500,000 year history of the modern edifice falls into four stages of alternating high and low magmatic output of subequal duration, but major and trace element compositions of eruptives show no correlation with volcano growth stages. Instead, the same spectrum of magmas (andesite to low-Si dacite) erupted throughout the history of the volcano with compositions in the same relative abundances. Superimposed on this seemingly null result are at least 6 brief but pronounced excursions in magma trace-element compositions. Concentrations of Zr, Ba, or Sr can double and then return to background values passing into and out of a single flow or flow-group. Some excursions are tightly bracketed by mapping and by measured ages and have durations no more than the geochronologic measurement precision of about 10,000 years. True excursion durations are potentially much shorter. The brevity and abrupt onsets and cessations of these compositional excursions are evidence against the presence of a sizeable, long-lived magma reservoir anywhere beneath the volcano, including a MASH zone in the lower crust, that would have attenuated, dampened, and homogenized compositional excursions introduced into the magmatic system. Instead, we take 10,000 years as a probable upper limit to the average residence time of magma batches transiting the crustal portion of Mount Rainier's plumbing system. A consistent scenario is that parental magmas enter the crust, differentiate, assimilate, and either erupt or solidify in less than 10,000 years. Geochronologic evidence from much larger magmatic systems (Reid and coworkers, Long Valley, Yellowstone) suggests that more productive systems can have much longer average residence times than modestly active arc stratovolcanoes like Mt. Rainier.

Instrumentation in remote and dangerous settings; examples using data from GPS “spider” deployments during the 2004-2005 eruption of Mount St. Helens, Washington: Chapter 16 in A volcano rekindled: the renewed eruption of Mount St. Helens, 2004-2006

USGS Publications Warehouse

LaHusen, Richard G.; Swinford, Kelly J.; Logan, Matthew; Lisowski, Michael; Sherrod, David R.; Scott, William E.; Stauffer, Peter H.

2008-01-01

Self-contained, single-frequency GPS instruments fitted on lightweight stations suitable for helicopter-sling payloads became a critical part of volcano monitoring during the September 2004 unrest and subsequent eruption of Mount St. Helens. Known as “spiders” because of their spindly frames, the stations were slung into the crater 29 times from September 2004 to December 2005 when conditions at the volcano were too dangerous for crews to install conventional equipment. Data were transmitted in near-real time to the Cascades Volcano Observatory in Vancouver, Washington. Each fully equipped unit cost about $2,500 in materials and, if not destroyed by natural events, was retrieved and redeployed as needed. The GPS spiders have been used to track the growth and decay of extruding dacite lava (meters per day), thickening and accelerated flow of Crater Glacier (meters per month), and movement of the 1980-86 dome from pressure and relaxation of the newly extruding lava dome (centimeters per day).

USGS VDP Infrasound Sensor Evaluation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Slad, George William; Merchant, Bion J.

2016-10-01

Sandia National Laboratories has tested and evaluated two infrasound sensors, the model VDP100 and VDP250, built in-house at the USGS Cascades Volcano Observatory. The purpose of the infrasound sensor evaluation was to determine a measured sensitivity, self-noise, dynamic range and nominal transfer function. Notable features of the VDP sensors include novel and durable construction and compact size.

Long-term multi-hazard assessment for El Misti volcano (Peru)

NASA Astrophysics Data System (ADS)

Sandri, Laura; Thouret, Jean-Claude; Constantinescu, Robert; Biass, Sébastien; Tonini, Roberto

2014-02-01

We propose a long-term probabilistic multi-hazard assessment for El Misti Volcano, a composite cone located <20 km from Arequipa. The second largest Peruvian city is a rapidly expanding economic centre and is classified by UNESCO as World Heritage. We apply the Bayesian Event Tree code for Volcanic Hazard (BET_VH) to produce probabilistic hazard maps for the predominant volcanic phenomena that may affect c.900,000 people living around the volcano. The methodology accounts for the natural variability displayed by volcanoes in their eruptive behaviour, such as different types/sizes of eruptions and possible vent locations. For this purpose, we treat probabilistically several model runs for some of the main hazardous phenomena (lahars, pyroclastic density currents (PDCs), tephra fall and ballistic ejecta) and data from past eruptions at El Misti (tephra fall, PDCs and lahars) and at other volcanoes (PDCs). The hazard maps, although neglecting possible interactions among phenomena or cascade effects, have been produced with a homogeneous method and refer to a common time window of 1 year. The probability maps reveal that only the north and east suburbs of Arequipa are exposed to all volcanic threats except for ballistic ejecta, which are limited to the uninhabited but touristic summit cone. The probability for pyroclastic density currents reaching recently expanding urban areas and the city along ravines is around 0.05 %/year, similar to the probability obtained for roof-critical tephra loading during the rainy season. Lahars represent by far the most probable threat (around 10 %/year) because at least four radial drainage channels can convey them approximately 20 km away from the volcano across the entire city area in heavy rain episodes, even without eruption. The Río Chili Valley represents the major concern to city safety owing to the probable cascading effect of combined threats: PDCs and rockslides, dammed lake break-outs and subsequent lahars or floods. Although this study does not intend to replace the current El Misti hazard map, the quantitative results of this probabilistic multi-hazard assessment can be incorporated into a multi-risk analysis, to support decision makers in any future improvement of the current hazard evaluation, such as further land-use planning and possible emergency management.

Gravity, magnetic, and radiometric data for Newberry Volcano, Oregon, and vicinity

USGS Publications Warehouse

Wynn, Jeff

2014-01-01

Newberry Volcano in central Oregon is a 3,100-square-kilometer (1,200-square-mile) shield-shaped composite volcano, occupying a location east of the main north-south trend of the High Cascades volcanoes and forming a transition between the High Lava Plains subprovince of the Basin and Range Province to the east and the Cascade Range to the west. Magnetic, gravity, and radiometric data have been gathered and assessed for the region around the volcano. These data have widely varying quality and resolution, even within a given dataset, and these limitations are evaluated and described in this release. Publicly available gravity data in general are too sparse to permit detailed modeling except along a few roads with high-density coverage. Likewise, magnetic data are also unsuitable for all but very local modeling, primarily because available data consist of a patchwork of datasets with widely varying line-spacing. Gravity data show only the broadest correlation with mapped geology, whereas magnetic data show moderate correlation with features only in the vicinity of Newberry Caldera. At large scales, magnetic data correlate poorly with both geologic mapping and gravity data. These poor correlations are largely due to the different sensing depths of the two potential fields methods, which respond to physical properties deeper than the surficial geology. Magnetic data derive from rocks no deeper than the Curie-point isotherm depth (10 to 15 kilometers, km, maximum), whereas gravity data reflect density-contrasts to 100 to 150 km depths. Radiometric data from the National Uranium Resource Evaluation (NURE) surveys of the 1980s have perhaps the coarsest line-spacing of all (as much as 10 km between lines) and are extremely “noisy” for several reasons inherent to this kind of data. Despite its shallow-sensing character, only a few larger anomalies in the NURE data correlate well with geologic mapping. The purpose of this data series release is to collect and place the available geophysical data in the hands of other investigators in a readily comprehensible form. All data-compilation, splicing, filtering, and overlay-map displays were accomplished with the commercial Geosoft™ system, Advanced Option. Images are provided in both JPG and PDF formats.

Real-time Seismic Amplitude Measurement (RSAM): a volcano monitoring and prediction tool

USGS Publications Warehouse

Endo, E.T.; Murray, T.

1991-01-01

Seismicity is one of the most commonly monitored phenomena used to determine the state of a volcano and for the prediction of volcanic eruptions. Although several real-time earthquake-detection and data acquisition systems exist, few continuously measure seismic amplitude in circumstances where individual events are difficult to recognize or where volcanic tremor is prevalent. Analog seismic records provide a quick visual overview of activity; however, continuous rapid quantitative analysis to define the intensity of seismic activity for the purpose of predicing volcanic eruptions is not always possible because of clipping that results from the limited dynamic range of analog recorders. At the Cascades Volcano Observatory, an inexpensive 8-bit analog-to-digital system controlled by a laptop computer is used to provide 1-min average-amplitude information from eight telemetered seismic stations. The absolute voltage level for each station is digitized, averaged, and appended in near real-time to a data file on a multiuser computer system. Raw realtime seismic amplitude measurement (RSAM) data or transformed RSAM data are then plotted on a common time base with other available volcano-monitoring information such as tilt. Changes in earthquake activity associated with dome-building episodes, weather, and instrumental difficulties are recognized as distinct patterns in the RSAM data set. RSAM data for domebuilding episodes gradually develop into exponential increases that terminate just before the time of magma extrusion. Mount St. Helens crater earthquakes show up as isolated spikes on amplitude plots for crater seismic stations but seldom for more distant stations. Weather-related noise shows up as low-level, long-term disturbances on all seismic stations, regardless of distance from the volcano. Implemented in mid-1985, the RSAM system has proved valuable in providing up-to-date information on seismic activity for three Mount St. Helens eruptive episodes from 1985 to 1986 (May 1985, May 1986, and October 1986). Tiltmeter data, the only other telemetered geophysical information that was available for the three dome-building episodes, is compared to RSAM data to show that the increase in RSAM data was related to the transport of magma to the surface. Thus, if tiltmeter data is not available, RSAM data can be used to predict future magmatic eruptions at Mount St. Helens. We also recognize the limitations of RSAm data. Two examples of RSAM data associated with phreatic or shallow phreatomagmatic explosions were not preceded by the same increases in RSAM data or changes in tilt associated with the three dome-building eruptions. ?? 1991 Springer-Verlag.

TECTONIC VERSUS VOLCANIC ORIGIN OF THE SUMMIT DEPRESSION AT MEDICINE LAKE VOLCANO, CALIFORNIA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mark Leon Gwynn

Medicine Lake Volcano is a Quaternary shield volcano located in a tectonically complex and active zone at the transition between the Basin and Range Province and the Cascade Range of the Pacific Province. The volcano is topped by a 7x12 km elliptical depression surrounded by a discontinuous constructional ring of basaltic to rhyolitic lava flows. This thesis explores the possibility that the depression may have formed due to regional extension (rift basin) or dextral shear (pull-apart basin) rather than through caldera collapse and examines the relationship between regional tectonics and localized volcanism. Existing data consisting of temperature and magnetotelluric surveys,more » alteration mineral studies, and core logging were compiled and supplemented with additional core logging, field observations, and fault striae studies in paleomagnetically oriented core samples. These results were then synthesized with regional fault data from existing maps and databases. Faulting patterns near the caldera, extension directions derived from fault striae P and T axes, and three-dimensional temperature and alteration mineral models are consistent with slip across arcuate ring faults related to magma chamber deflation during flank eruptions and/or a pyroclastic eruption at about 180 ka. These results are not consistent with a rift or pull-apart basin. Limited subsidence can be attributed to the relatively small volume of ash-flow tuff released by the only known major pyroclastic eruption and is inconsistent with the observed topographic relief. The additional relief can be explained by constructional volcanism. Striae from unoriented and oriented core, augmented by striae measurements in outcrop suggest that Walker Lane dextral shear, which can be reasonably projected from the southeast, has probably propagated into the Medicine Lake area. Most volcanic vents across Medicine Lake Volcano strike north-south, suggesting they are controlled by crustal weakness related to Basin and Range extension. Interaction of dextral shear, Basin and Range extension, and the zone of crustal weakness expressed as the Mount Shasta-Medicine Lake volcanic highland controlled the location and initiation of Medicine Lake Volcano at about 500 ka.« less

Tectonic versus volcanic origin of the summit depression at Medicine Lake Volcano, California

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mark Leon Gwynn

Medicine Lake Volcano is a Quaternary shield volcano located in a tectonically complex and active zone at the transition between the Basin and Range Province and the Cascade Range of the Pacific Province. The volcano is topped by a 7x12 km elliptical depression surrounded by a discontinuous constructional ring of basaltic to rhyolitic lava flows. This thesis explores the possibility that the depression may have formed due to regional extension (rift basin) or dextral shear (pull-apart basin) rather than through caldera collapse and examines the relationship between regional tectonics and localized volcanism. Existing data consisting of temperature and magnetotelluric surveys,more » alteration mineral studies, and core logging were compiled and supplemented with additional core logging, field observations, and fault striae studies in paleomagnetically oriented core samples. These results were then synthesized with regional fault data from existing maps and databases. Faulting patterns near the caldera, extension directions derived from fault striae P and T axes, and three-dimensional temperature and alteration mineral models are consistent with slip across arcuate ring faults related to magma chamber deflation during flank eruptions and/or a pyroclastic eruption at about 180 ka. These results are not consistent with a rift or pull-apart basin. Limited subsidence can be attributed to the relatively small volume of ash-flow tuff released by the only known major pyroclastic eruption and is inconsistent with the observed topographic relief. The additional relief can be explained by constructional volcanism. Striae from unoriented and oriented core, augmented by striae measurements in outcrop suggest that Walker Lane dextral shear, which can be reasonably projected from the southeast, has probably propagated into the Medicine Lake area. Most volcanic vents across Medicine Lake Volcano strike north-south, suggesting they are controlled by crustal weakness related to Basin and Range extension. Interaction of dextral shear, Basin and Range extension, and the zone of crustal weakness expressed as the Mount Shasta-Medicine Lake volcanic highland controlled the location and initiation of Medicine Lake Volcano at about 500 ka.« less

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

USGS Publications Warehouse

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

2011-01-01

The year 2012 marks the centennial of the Hawaiian Volcano Observatory (HVO). With the support and cooperation of visionaries, financiers, scientists, and other individuals and organizations, HVO has successfully achieved 100 years of continuous monitoring of Hawaiian volcanoes. As we celebrate this milestone anniversary, we express our sincere mahalo—thanks—to the people who have contributed to and participated in HVO’s mission during this past century. First and foremost, we owe a debt of gratitude to the late Thomas A. Jaggar, Jr., the geologist whose vision and efforts led to the founding of HVO. We also acknowledge the pioneering contributions of the late Frank A. Perret, who began the continuous monitoring of Kīlauea in 1911, setting the stage for Jaggar, who took over the work in 1912. Initial support for HVO was provided by the Massachusetts Institute of Technology (MIT) and the Carnegie Geophysical Laboratory, which financed the initial cache of volcano monitoring instruments and Perret’s work in 1911. The Hawaiian Volcano Research Association, a group of Honolulu businessmen organized by Lorrin A. Thurston, also provided essential funding for HVO’s daily operations starting in mid-1912 and continuing for several decades. Since HVO’s beginning, the University of Hawaiʻi (UH), called the College of Hawaii until 1920, has been an advocate of HVO’s scientific studies. We have benefited from collaborations with UH scientists at both the Hilo and Mänoa campuses and look forward to future cooperative efforts to better understand how Hawaiian volcanoes work. The U.S. Geological Survey (USGS) has operated HVO continuously since 1947. Before then, HVO was under the administration of various Federal agencies—the U.S. Weather Bureau, at the time part of the Department of Agriculture, from 1919 to 1924; the USGS, which first managed HVO from 1924 to 1935; and the National Park Service from 1935 to 1947. For 76 of its first 100 years, HVO has been part of the USGS, the Nation’s premier Earth science agency. It currently operates under the direction of the USGS Volcano Science Center, which now supports five volcano observatories covering six U.S. areas—Hawaiʻi (HVO), Alaska and the Northern Mariana Islands (Alaska Volcano Observatory), Washington and Oregon (Cascades Volcano Observatory), California (California Volcano Observatory), and the Yellowstone region (Yellowstone Volcano Observatory). Although the National Park Service (NPS) managed HVO for only 12 years, HVO has enjoyed a close working relationship with Hawaiʻi Volcanoes National Park (named Hawaii National Park until 1961) since the park’s founding in 1916. Today, as in past years, the USGS and NPS work together to ensure the safety and education of park visitors. We are grateful to all park employees, particularly Superintendent Cindy Orlando and Chief Ranger Talmadge Magno and their predecessors, for their continuing support of HVO’s mission. HVO also works closely with the Hawaiʻi County Civil Defense. During volcanic and earthquake crises, we have appreciated the support of civil defense staff, especially that of Harry Kim and Quince Mento, who administered the agency during highly stressful episodes of Kīlauea's ongoing eruption. Our work in remote areas on Hawaiʻi’s active volcanoes is possible only with the able assistance of Hawaiʻi County and private pilots who have safely flown HVO staff to eruption sites through the decades. A special mahalo goes to David Okita, who has been HVO’s principal helicopter pilot for more than two decades. Many commercial and Civil Air Patrol pilots have also assisted HVO by reporting their observations during various eruptive events. Hawaiʻi’s news media—print, television, radio, and online sources—do an excellent job of distributing volcano and earthquake information to the public. Their assistance is invaluable to HVO, especially during times of crisis. HVO’s efforts to provide timely and accurate scientific information about Hawaiian volcanoes and earthquakes succeed only because of you, our receptive and keenly aware public. By following the activity of Hawaiʻi’s active volcanoes through our daily eruption updates posted on the HVO website, viewing HVO webcam images, reading our weekly “Volcano Watch” articles, and attending our public lectures, you help us to ensure that you can live safely with Hawaiʻi’s dynamic volcanoes. To everyone who has shared in HVO’s reaching this milestone—100 years of continuous volcano monitoring—we extend our deepest gratitude. Mahalo nui loa!

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

USGS Publications Warehouse

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

2008-01-01

Mount St. Helens has erupted more frequently than any other volcano in the Cascade Range during the past 4,000 years. The volcano has exhibited a variety of eruption styles?explosive eruptions of pumice and ash, slow but continuous extrusions of viscous lava, and eruptions of fluid lava. Evidence of the volcano?s older eruptions is recorded in the rocks that build and the deposits that flank the mountain. Eruptions at Mount St. Helens over the past three decades serve as reminders of the powerful geologic forces that are reshaping the landscape of the Pacific Northwest. On May 18, 1980, a massive landslide and catastrophic explosive eruption tore away 2.7 cubic kilometers of the mountain and opened a gaping, north-facing crater. Lahars flowed more than 120 kilometers downstream, destroying bridges, roads, and buildings. Ash from the eruption fell as far away as western South Dakota. Reconstruction of the volcano began almost immediately. Between 1980 and 1986, 80 million cubic meters of viscous lava extruded episodically onto the crater floor, sometimes accompanied by minor explosions and small lahars. A lava dome grew to a height of 267 meters, taller than the highest buildings in the nearby city of Portland, Oregon. Crater Glacier formed in the deeply shaded niche between the 1980-86 lava dome and the south crater wall. Its tongues of ice flowed around the east and west sides of the dome. Between 1989 and 1991, multiple explosions of steam and ash rocked the volcano, possibly a result of infiltrating rainfall being heated in the still-hot interior of the dome and underlying crater floor. In September 2004, rising magma caused earthquake swarms and deformation of the crater floor and glacier, which indicated that Mount St. Helens might erupt again soon. On October 1, 2004, a steam and ash explosion signaled the beginning of a new phase of eruptive activity at the volcano. On October 11, hot rock reached the surface and began building a new lava dome immediately south of the 1980-86 lava dome. The erupting lava cleaved Crater Glacier in half and bulldozed it aside, causing thickening, crevassing, and rapid northward advance of the glacier?s east and west arms. Intermittent steam and ash explosions, some generating plumes that rose up to 11 kilometers, preceded and accompanied extrusion of the new lava dome, but ceased by early 2005. As the new dome grew, a series of large fins or spines of hot lava rose, some more than 100 meters high, and then crumbled producing sometimes spectacular rock falls. The largest of these rock falls generated dust or steam plumes that rose high above the crater rim. By February 2006, the new dome had grown to a volume similar to that of the 1980-86 lava dome; and by July 2007, the new dome had grown to a volume of 93 million cubic meters, exceeding the volume of the 1980-86 lava dome. The height of the new dome also exceeded that of the 1980-86 lava dome, and at its highest point (before collapse in 2005) reached to within 2 meters of the lowest point on the south crater rim. At this height, the new dome was taller than the Empire State Building in New York City. The new lava dome initially grew very quickly, at rates of 2 to 3 cubic meters (one small dump truck load) per second. If it had continued to grow at these rates for about 100 years, it would have replaced the volume of rock removed from the volcano during the May 18, 1980, eruption. However, the lava extrusion rate slowed throughout the eruption, and, by July 2007, it was oozing at a rate of 0.1 cubic meters per second. At that rate, it would take over 700 years to replace the volume of rock lost in 1980. Lava dome extrusion has continued into early 2008.

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

NASA Astrophysics Data System (ADS)

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.

Database for the Geologic Map of Upper Eocene to Holocene Volcanic and Related Rocks of the Cascade Range, Oregon

USGS Publications Warehouse

Nimz, Kathryn; Ramsey, David W.; Sherrod, David R.; Smith, James G.

2008-01-01

Since 1979, Earth scientists of the Geothermal Research Program of the U.S. Geological Survey have carried out multidisciplinary research in the Cascade Range. The goal of this research is to understand the geology, tectonics, and hydrology of the Cascades in order to characterize and quantify geothermal resource potential. A major goal of the program is compilation of a comprehensive geologic map of the entire Cascade Range that incorporates modern field studies and that has a unified and internally consistent explanation. This map is one of three in a series that shows Cascade Range geology by fitting published and unpublished mapping into a province-wide scheme of rock units distinguished by composition and age; map sheets of the Cascade Range in Washington (Smith, 1993) and California will complete the series. The complete series forms a guide to exploration and evaluation of the geothermal resources of the Cascade Range and will be useful for studies of volcano hazards, volcanology, and tectonics. This digital release contains all the information used to produce the geologic map published as U.S. Geological Survey Geologic Investigations Series I-2569 (Sherrod and Smith, 2000). The main component of this digital release is a geologic map database prepared using ArcInfo GIS. This release also contains files to view or print the geologic map and accompanying descriptive pamphlet from I-2569.

Blue Mountains Ecoregion: Chapter 16 in Status and trends of land change in the Western United States--1973 to 2000

USGS Publications Warehouse

Soulard, Christopher E.

2012-01-01

The Blue Mountains Ecoregion encompasses approximately 65,461 km² (25,275 mi²) of land bordered on the north by the Columbia Plateau Ecoregion, on the east by the Northern Rockies Ecoregion, on the south by the Snake River Basin and the Northern Basin and Range Ecoregions, and on the west by the Cascades and the Eastern Cascades Slopes and Foothills Ecoregions (fig. 1) (Omernik, 1987; U.S. Environmental Protection Agency, 1997). Most of the Blue Mountains Ecoregion is located within Oregon (83.5 percent); 13.8 percent is in Idaho, and 2.7 percent is in Washington. The Blue Mountains are composed of primarily Paleozoic volcanic rocks, with minor sedimentary, metamorphic, and granitic rocks. Lower mountains and numerous basin-and-range areas, as well as the lack of Quaternary-age volcanoes, distinguish the Blue Mountains from the adjacent Cascade Range (Thorson and others, 2003).

Geologic map of the Lassen region, Cascade Range, USA

USGS Publications Warehouse

Clynne, Michael; Muffler, L.J.

1990-01-01

A preliminary geologic map at 1:50,000 of the Lassen region encompasses 1400 km2. The map displays many small, monogenetic volcanoes of basalt to andesite as well as three major late Pliocene and Quaternary volcanic centers that have erupted products ranging from basaltic andesite to rhyolite. The youngest of these volcanic centers is the Lassen volcanic center, active from 600,000 years B.P. to the present. A major caldera formed at 400,000 years B.P. and has subsequently been filled with silicic lavas. The Lassen geothermal system, which consists of a central vapor-dominated reservoir at a temperature of 235??C underlain by a reservoir of hot water, is centered at Bumpass Hell within Lassen Volcanic National Park.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sherrod, D.R.; Smith, J.G.

Quaternary (2-0 Ma) extrusion rates change significantly along the Cascade Range volcanic arc. The extrusion rate north of Mount Rainier is about 0.21 km{sup 3} km{sup {minus}1} m.y.{sup {minus}1}; the rate in southern Washington and northern Oregon south to Mount Hood is about 1.6 km{sup 3} km{sup {minus}1} m.y.{sup {minus}1}; in central Oregon the rate is 3-6 km{sup 3} km{sup {minus}1}; and in northern California, the rate is 3.2 km{sup 3} km{sup {minus}1} m.y.{sup {minus}1}. Eruption style also changes along the arc but at latitudes different from rate changes. At the ends of the arc, volcanism is focused at isolatedmore » intermediate to silicic composite volcanoes. The composite volcanoes represent {approximately}30% of the total volume of the arc. Mafic volcanic fields partly ring some composite volcanoes, especially in the south. In contrast, volcanism is diffused in the middle of the arc, where numerous overlapping mafic shields and a few composite volcanoes have built a broad ridge. Contrasting eruption style may signify diffuse versus focused heat sources or may reflect changes in permeability to ascending magma along the arc.« less

High Resolution, Low Altitude Aeromagnetic and Electromagnetic Survey of Mt Rainier

USGS Publications Warehouse

Rystrom, V.L.; Finn, C.; Deszcz-Pan, Maryla

2000-01-01

In October 1996, the USGS conducted a high resolution airborne magnetic and electromagnetic survey in order to discern through-going sections of exposed altered rocks and those obscured beneath snow, vegetation and surficial unaltered rocks. Hydrothermally altered rocks weaken volcanic edifices, creating the potential for catastrophic sector collapses and ensuing formation of destructive volcanic debris flows. This data once compiled and interpreted, will be used to examine the geophysical properties of the Mt. Rainier volcano, and help assist the USGS in its Volcanic Hazards Program and at its Cascades Volcano Observatory. Aeromagnetic and electromagnetic data provide a means for seeing through surficial layers and have been tools for delineating structures within volcanoes. However, previously acquired geophysical data were not useful for small-scale geologic mapping. In this report, we present the new aeromagnetic and electromagnetic data, compare results from previously obtained, low-resolution aeromagnetic data with new data collected at a low-altitude and closely spaced flightlines, and provide information on potential problems with using high-resolution data.

Snow Peak, OR: Miocene and Pliocene Tholeiitic Volcanism in the Cascadia Forearc

NASA Astrophysics Data System (ADS)

Hatfield, A. K.; Kent, A. J.; Nielsen, R. L.; Rowe, M. C.; Duncan, R. A.

2007-12-01

Snow Peak is a voluminous (>150 km3), glacially dissected shield volcano located approximately 50 km southeast of Salem, OR, with a summit height of 1,310 m above sea level. Snow Peak lies approximately 60 km west of the current High Cascade arc axis. Lavas from the southeast face of Snow Peak have been previously dated using K-Ar at ~3 Ma. New Ar-Ar dating indicates that lavas from the northwest face are ~5.4 Ma, and the summit plug is ~6 Ma. Snow Peak volcanics unconformably overlie western Cascade volcanics aged from middle to late Miocene (~10- 17 Ma). The age of Snow Peak is broadly contemporaneous with the initiation of modern High Cascade volcanism. Snow Peak's location provides a rare opportunity to study magmas produced within the modern High Cascades forearc region. The goal of this investigation is to characterize the composition and timing of volcanism at Snow Peak and the role of volatiles in magma genesis. Hypotheses for the formation of Snow Peak include flux melting associated with the Cascadia subduction zone and/or decompression melting associated with extensional faulting. Preliminary geochemical data on the basalts from Snow Peak indicate that they are low-to-medium-K tholeiites (SiO2 47.9-51.7 wt.%, MgO 5.5- 8.3 wt.%, K2O, 0.36-0.55 wt.%) and that they range from primitive to moderately evolved (Mg# 0.51-0.61). Common phenocryst phases are plagioclase, olivine, and clinopyroxene. Textures are typically hypocrystalline, and fine-grained to porphyritic. Mantle-normalized multi-element plots indicate Snow Peak lavas are generally HFSE depleted and LILE enriched. These data are consistent with a preliminary interpretation of a subduction zone signature, yet the major element composition most closely resembles high alumina olivine tholeiite (HAOT), more indicative of extensional environments. The degree of LILE enrichment is significantly lower than in calc alkaline lavas from the High Cascades and western Cascades. Determining the petrogenesis of this forearc center will include a comprehensive analysis of the volcano's major and trace element geochemistry, and additional age dating to constrain eruption rates. Direct measurement of volatiles in olivine-hosted melt inclusions will complement the major and trace element geochemistry in order to measure pre-eruptive water contents.

Period doubling and other nonlinear phenomena in volcanic earthquakes and tremor

USGS Publications Warehouse

Julian, B.R.

2000-01-01

Evidence of subharmonic period-doubling cascades has recently been recognized in seismograms of volcanic tremor from several volcanoes. This phenomenon occurs only in nonlinear systems, and is the commonest route by which such systems change from periodic to chaotic behavior. It is predicted to occur in a model of volcanic tremor excitation by flow-induced vibration, and it might well also occur in other volcano-seismic source process. If the possibility of period doubling is not taken into account in interpreting spectra of tremor and long-period earthquakes, then low-frequency "sub-harmonic" oscillations may be mis-identified as normal modes of a linear acoustic resonator, leading to errors of an order of magnitude or more in inferred magma-body dimensions. This example illustrates the importance of nonlinear phenomena in attempts to understand volcano-seismic phenomena physically. Linear systems are fundamentally incapable of causing earthquakes or exciting tremor, so nonlinearity is essential to any theory of volcano-seismic phenomena. Nonlinear processes are in many respects qualitatively different from linear ones. A few of their characteristics that might be relevant in volcanoes include the possibility: (1) that damping might increase, rather than decrease, oscillation frequencies; and (2) that these frequencies might be functions of the amplitude of oscillation, so that temporal variations in spectral peak frequencies might not be manifestations of changes of conditions within the magmatic system.

Rebuilding Mount St. Helens

USGS Publications Warehouse

Schilling, Steve P.; Ramsey, David W.; Messerich, James A.; Thompson, Ren A.

2006-01-01

On May 18, 1980, Mount St. Helens, Washington exploded in a spectacular and devastating eruption that shocked the world. The eruption, one of the most powerful in the history of the United States, removed 2.7 cubic kilometers of rock from the volcano's edifice, the bulk of which had been constructed by nearly 4,000 years of lava-dome-building eruptions. In seconds, the mountain's summit elevation was lowered from 2,950 meters to 2,549 meters, leaving a north-facing, horseshoe-shaped crater over 2 kilometers wide. Following the 1980 eruption, Mount St. Helens remained active. A large lava dome began episodically extruding in the center of the volcano's empty crater. This dome-building eruption lasted until 1986 and added about 80 million cubic meters of rock to the volcano. During the two decades following the May 18, 1980 eruption, Crater Glacier formed tongues of ice around the east and west sides of the lava dome in the deeply shaded niche between the lava dome and the south crater wall. Long the most active volcano in the Cascade Range with a complex 300,000-year history, Mount St. Helens erupted again in the fall of 2004 as a new period of dome building began within the 1980 crater. Between October 2004 and February 2006, about 80 million cubic meters of dacite lava erupted immediately south of the 1980-86 lava dome. The erupting lava separated the glacier into two parts, first squeezing the east arm of the glacier against the east crater wall and then causing equally spectacular crevassing and broad uplift of the glacier's west arm. Vertical aerial photographs document dome growth and glacier deformation. These photographs enabled photogrammetric construction of a series of high-resolution digital elevation models (DEMs) showing changes from October 4, 2004 to February 9, 2006. From the DEMs, Geographic Information Systems (GIS) applications were used to estimate extruded volumes and growth rates of the new lava dome. The DEMs were also used to quantify dome height variations, size of the magma conduit opening, and the mechanics of dome emplacement. Previous lava-dome-building eruptions at the volcano have persisted intermittently for years to decades. Over time, such events constructed much of the cone-shaped mountain seen prior to the May 18, 1980 eruption. Someday, episodic dome growth may eventually rebuild Mount St. Helens to its pre-1980 form.

Active Deformation of Etna Volcano Combing IFSAR and GPS data

NASA Technical Reports Server (NTRS)

Lundgren, Paul

1997-01-01

The surface deformation of an active volcano is an important indicator of its eruptive state and its hazard potential. Mount Etna volcano in Sicily is a very active volcano with well documented eruption episodes.

Bathymetric, geophysical and geologic sample data from Medicine Lake, Siskiyou County, northern California

USGS Publications Warehouse

Childs, Jonathan R.; Lowenstern, J. B.; Phillips, R.L.; Hart, P.E.; Rytuba, J.J.; Barron, J.A.; Starratt, S.W.; Spaulding, Sarah

2000-01-01

In September, 1999, the U.S. Geological Survey acquired high-resolution bathymetry, seismic reflection profiles, and geologic sample data from Medicine Lake, a high altitude (2,036 m) lake located within the summit caldera/basin at Medicine Lake volcano (MLV), a dormant Quaternary shield volcano located in the Cascade Range, 50 km northeast of Mt. Shasta. It last erupted less than 1000 years ago.The purpose of this work was to assess whether sediments in the lake might provide a high-resolution record of the climate, volcanic and geochemical (particularly mercury) history of the region. We are still working with our data to assess whether the sediments are appropriate for further study. This report provides a summary of what we have learned to date.

Volcanology by Courier: Science in Stamps.

ERIC Educational Resources Information Center

Glenn, William H.

1981-01-01

Summarized are five activities involving collection of postage stamps picturing volcanoes or related scenes for use as part of or at the conclusion of the study of volcanoes. Activity topics include volcanic features, location of volcanoes, related land features where volcanoes are not located, and making one's own volcano stamps. (DS)

Electrical structure of Newberry Volcano, Oregon

USGS Publications Warehouse

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

1988-01-01

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

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

NASA Technical Reports Server (NTRS)

2004-01-01

Mount Saint Helens is a prime example of how Earth's topographic form can greatly change even within our lifetimes. The mountain is one of several prominent volcanoes of the Cascade Range that stretches from British Columbia, Canada, southward through Washington, Oregon, and into northern California. Mount Adams (left background) and Mount Hood (right background) are also seen in this view, which was created entirely from elevation data produced by the Shuttle Radar Topography Mission.

Prior to 1980, Mount Saint Helens had a shape roughly similar to other Cascade peaks, a tall, bold, irregular conic form that rose to 2950 meters (9677 feet). However, the explosive eruption of May 18, 1980, caused the upper 400 meters (1300 feet) of the mountain to collapse, slide, and spread northward, covering much of the adjacent terrain (lower left), leaving a crater atop the greatly shortened mountain. Subsequent eruptions built a volcanic dome within the crater, and the high rainfall of this area lead to substantial erosion of the poorly consolidated landslide material.

Eruptions at Mount Saint Helens subsided in 1986, but renewed volcanic activity here and at other Cascade volcanoes is inevitable. Predicting such eruptions still presents challenges, but migration of magma within these volcanoes often produces distinctive seismic activity and minor but measurable topographic changes that can give warning of a potential eruption.

Three visualization methods were combined to produce this image: shading of topographic slopes, color coding of topographic height, and then projection into a perspective view. The shade image was derived by computing topographic slope in the northeast-southwest (left to right) direction, so that northeast slopes appear bright and southwest slopes appear dark. Color coding is directly related to topographic height, with green at the lower elevations, rising through yellow and tan, to white at the highest elevations. The perspective view simulates the geometry of the surface as it would be viewed on a clear day.

Elevation data used in this image were acquired by the Shuttle Radar Topography Mission aboard the Space Shuttle Endeavour, launched on Feb. 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect 3-D measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter (approximately 200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between NASA, the National Geospatial-Intelligence Agency (NGA) of the U.S. Department of Defense and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., for NASA's NASA's Science Mission Directorate, Washington, D.C.

Size: View distance about 150 km (about 100 miles) Location: 46.2 degrees North latitude, 122.2 degrees West longitude Orientation: View Southeast Image Data: Shaded and colored SRTM elevation model Date Acquired: February 2000

Late Cenozoic Magmatic and Tectonic Evolution of the Ancestral Cascade Arc in the Bodie Hills, California and Nevada: Insights from Integrated Geologic, Geophysical, Geochemical and Geochronologic Studies

NASA Astrophysics Data System (ADS)

John, D. A.; du Bray, E. A.; Box, S. E.; Blakely, R. J.; Fleck, R. J.; Vikre, P. G.; Cousens, B.; Moring, B. C.

2012-12-01

Geologic mapping integrated with new geophysical, geochemical, and geochronologic data characterize the evolution of Bodie Hills volcanic field (BHVF), a long-lived eruptive center in the southern part of the ancestral Cascade arc. The ~700 km2 field was a locus of magmatic activity from ~15 to 8 Ma. It includes >25 basaltic andesite to trachyandesite stratovolcanoes and silicic trachyandesite to rhyolite dome complexes. The southeastern part of the BHVF is overlain by the ~3.9 to 0.1 Ma, post-arc Aurora Volcanic Field. Long-lived BHVF magmatism was localized by crustal-scale tectonic features, including the Precambrian continental margin, the Walker Lane, the Basin and Range Province, and the Mina deflection. BHVF eruptive activity occurred primarily during 3 stages: 1) dominantly trachyandesite stratovolcanoes (~15.0 to 12.9 Ma), 2) coalesced trachydacite and rhyolite lava domes and trachyandesite stratovolcanoes (~11.6 to 9.7 Ma), and 3) dominantly silicic trachyandesite to dacite lava dome complexes (~9.2 to 8.0 Ma). Small rhyolite domes were emplaced at ~6 Ma. Relatively mafic stratovolcanoes surrounded by debris flow aprons lie on the margins of the BHVF, whereas more silicic dome fields occupy its center. Detailed gravity and aeromagnetic data suggest the presence of unexposed cogenetic granitic plutons beneath the center of the BHVF. Isotopic compositions of BHVF rocks are generally more radiogenic with decreasing age (e.g., initial Sr isotope values increase from ~0.7049 to 0.7061), which suggests progressively greater magma contamination by crustal components during evolution of the BHVF. Approximately circular, polygenetic volcanoes and scarcity of dikes suggest a low differential horizontal stress field during BHVF formation. Extensive alluvial gravel deposits that grade laterally into fluvial gravels and finer grained lacustrine sediments and the westerly sourced Eureka Valley Tuff (EVT; ~9.4 Ma) blanket large parts of the BHVF. The earliest sediments (≥11.5 Ma to ~9.4 Ma) fill paleotopography around and between older volcanic centers, lap onto the NE part of the BHVF, extend east into Fletcher Valley, and are overlain by EVT. The Fletcher Valley sediments probably mark the beginning of regional Basin-Range extension. Post-EVT alluvial-fan, fluvial, and lacustrine deposits on the NW margin of the Bodie Hills apparently are related to development of the flanking Bridgeport Valley graben to the west. No major through-going faults are recognized in the Bodie Hills, and BHVF volcanoes are only gently (<25°) tilted and little extended. Dominantly intermediate to silicic stratovolcanoes and dome complexes in the BHVF are similar to other long-lived, ancestral Cascade arc eruptive centers in the western Basin and Range (e.g., Virginia Range, Tonopah, Goldfield) and differ from areas farther west and north (e.g., central Sierra Nevada, Lake Tahoe, Warner Range) characterized by more mafic compositions (mostly basalt to andesite), mixed strato- and shield volcanoes, and small lava domes. These differences likely reflect thicker crust that inhibited direct ascent of mafic, mantle-derived magma, thereby promoting long-lived magma reservoirs with extensive differentiation and crustal contamination at shallow depths.

Three active volcanoes in China and their hazards

NASA Astrophysics Data System (ADS)

Wei, H.; Sparks, R. S. J.; Liu, R.; Fan, Q.; Wang, Y.; Hong, H.; Zhang, H.; Chen, H.; Jiang, C.; Dong, J.; Zheng, Y.; Pan, Y.

2003-02-01

The active volcanoes in China are located in the Changbaishan area, Jingbo Lake, Wudalianchi, Tengchong and Yutian. Several of these volcanoes have historical records of eruption and geochronological evidence of Holocene activity. Tianchi Volcano is a well-preserved Cenozoic polygenetic central volcano, and, due to its recent history of powerful explosive eruptions of felsic magmas, with over 100,000 people living on its flanks is a high-risk volcano. Explosive eruptions at 4000 and 1000 years BP involved plinian and ignimbrite phases. The Millennium eruption (1000 years BP) involved at least 20-30 km 3 of magma and was large enough to have a global impact. There are 14 Cenozoic monogenetic scoria cones and associated lavas with high-K basalt composition in the Wudalianchi volcanic field. The Laoheishan and Huoshaoshan cones and related lavas were formed in 1720-1721 and 1776 AD. There are three Holocene volcanoes, Dayingshan, Maanshan, and Heikongshan, among the 68 Quaternary volcanoes in the Tengchong volcanic province. Three of these volcanoes are identified as active, based on geothermal activity, geophysical evidence for magma, and dating of young volcanic rocks. Future eruptions of these Chinese volcanoes pose a significant threat to hundreds of thousands of people and are likely to cause substantial economic losses.

USGS GNSS Applications to Volcano Disaster Response and Hazard Mitigation

NASA Astrophysics Data System (ADS)

Lisowski, M.; McCaffrey, R.

2015-12-01

Volcanic unrest is often identified by increased rates of seismicity, deformation, or the release of volcanic gases. Deformation results when ascending magma accumulates in crustal reservoirs, creates new pathways to the surface, or drains from magma reservoirs to feed an eruption. This volcanic deformation is overprinted by deformation from tectonic processes. GNSS monitoring of volcanoes captures transient volcanic deformation and steady and transient tectonic deformation, and we use the TDEFNODE software to unravel these effects. We apply the technique on portions of the Cascades Volcanic arc in central Oregon and in southern Washington that include a deforming volcano. In central Oregon, the regional TDEFNODE model consists of several blocks that rotate and deform internally and a decaying inflationary volcanic pressure source to reproduce the crustal bulge centered ~5 km west of South Sister. We jointly invert 47 interferograms that cover the interval from 1992 to 2010, as well as 2001 to 2015 continuous GNSS (cGNSS) and survey-mode (sGNSS) time series from stations in and around the Three Sisters, Newberry, and Crater Lake areas. A single, smoothly-decaying ~5 km deep spherical or prolate spheroid volcanic pressure source activated around 1998 provides the best fit to the combined geodetic data. In southern Washington, GNSS displacement time-series track decaying deflation of a ~8 km deep magma reservoir that fed the 2004 to 2008 eruption of Mount St. Helens. That deformation reversed when it began to recharge after the eruption ended. Offsets from slow slip events on the Cascadia subduction zone punctuate the GNSS displacement time series, and we remove them by estimating source parameters for these events. This regional TDEFNODE model extends from Mount Rainier south to Mount Hood, and additional volcanic sources could be added if these volcanoes start deforming. Other TDEFNODE regional models are planned for northern Washington (Mount Baker and Glacier Peak), northern California (Mount Shasta, Medicine Lake, Lassen Peak), and Long Valley. These models take advantage of the data from dense GNSS networks, they provide source parameters for volcanic and tectonic transients, and can be used to discriminate possible short- and long-term volcano- tectonic interactions.

A Conceptual Model of Future Volcanism at Medicine Lake Volcano, California - With an Emphasis on Understanding Local Volcanic Hazards

NASA Astrophysics Data System (ADS)

Molisee, D. D.; Germa, A.; Charbonnier, S. J.; Connor, C.

2017-12-01

Medicine Lake Volcano (MLV) is most voluminous of all the Cascade Volcanoes ( 600 km3), and has the highest eruption frequency after Mount St. Helens. Detailed mapping by USGS colleagues has shown that during the last 500,000 years MLV erupted >200 lava flows ranging from basalt to rhyolite, produced at least one ash-flow tuff, one caldera forming event, and at least 17 scoria cones. Underlying these units are 23 additional volcanic units that are considered to be pre-MLV in age. Despite the very high likelihood of future eruptions, fewer than 60 of 250 mapped volcanic units (MLV and pre-MLV) have been dated reliably. A robust set of eruptive ages is key to understanding the history of the MLV system and to forecasting the future behavior of the volcano. The goals of this study are to 1) obtain additional radiometric ages from stratigraphically strategic units; 2) recalculate recurrence rate of eruptions based on an augmented set of radiometric dates; and 3) use lava flow, PDC, ash fall-out, and lahar computational simulation models to assess the potential effects of discrete volcanic hazards locally and regionally. We identify undated target units (units in key stratigraphic positions to provide maximum chronological insight) and obtain field samples for radiometric dating (40Ar/39Ar and K/Ar) and petrology. Stratigraphic and radiometric data are then used together in the Volcano Event Age Model (VEAM) to identify changes in the rate and type of volcanic eruptions through time, with statistical uncertainty. These newly obtained datasets will be added to published data to build a conceptual model of volcanic hazards at MLV. Alternative conceptual models, for example, may be that the rate of MLV lava flow eruptions are nonstationary in time and/or space and/or volume. We explore the consequences of these alternative models on forecasting future eruptions. As different styles of activity have different impacts, we estimate these potential effects using simulation. The results of this study will improve the existing MLV hazard assessment in hopes of mitigating casualties and social impact should an eruption occur at MLV.

Long-term changes in quiescent degassing at Mount Baker Volcano, Washington, USA; Evidence for a stalled intrusion in 1975 and connection to a deep magma source

USGS Publications Warehouse

Werner, Cynthia A.; Evans, William C.; Poland, Michael P.; Doukas, Michael P.; Tucker, D.S.

2009-01-01

Long-term changes have occurred in the chemistry, isotopic ratios, and emission rates of gas at Mount Baker volcano following a major thermal perturbation in 1975. In mid-1975 a large pulse in sulfur and carbon dioxide output was observed both in emission rates and in fumarole samples. Emission rates of CO2 and H2S were ??? 950 and 112??t/d, respectively, in 1975; these decreased to ??? 150 and < 1??t/d by 2007. During the peak of the activity the C/S ratio was the lowest ever observed in the Cascade Range and similar to magmatic signatures observed at other basaltic-andesite volcanoes worldwide. Increases in the C/S ratio and decreases in the CO2/CH4 ratio since 1975 suggest a long steady trend back toward a more hydrothermal gas signature. The helium isotope ratio is very high (> 7??Rc/RA), but has declined slightly since the mid-1970s, and ??13C-CO2 has decreased by ??? 1??? over time. Both trends are expected from a gradually crystallizing magma. While other scenarios are investigated, we conclude that magma intruded the mid- to shallow-crust beneath Mount Baker during the thermal awakening of 1975. Since that time, evidence for fresh magma has waned, but the continued emission of CO2 and the presence of a long-term hydrothermal system leads us to suspect some continuing connection between the surface and deep convecting magma.

Catalog of Mount St. Helens 2004-2007 Dome Samples with Major- and Trace-Element Chemistry

USGS Publications Warehouse

Thornber, Carl R.; Pallister, John S.; Rowe, Michael C.; McConnell, Siobhan; Herriott, Trystan M.; Eckberg, Alison; Stokes, Winston C.; Cornelius, Diane Johnson; Conrey, Richard M.; Hannah, Tammy; Taggart, Joseph E.; Adams, Monique; Lamothe, Paul J.; Budahn, James R.; Knaack, Charles M.

2008-01-01

Sampling and analysis of eruptive products at Mount St. Helens is an integral part of volcano monitoring efforts conducted by the U.S. Geological Survey?s Cascades Volcano Observatory (CVO). The objective of our eruption sampling program is to enable petrological assessments of pre-eruptive magmatic conditions, critical for ascertaining mechanisms for eruption triggering and forecasting potential changes in eruption behavior. This report provides a catalog of near-vent lithic debris and new dome-lava collected during 34 intra-crater sampling forays throughout the October 2004 to October 2007 (2004?7) eruptive interval at Mount St. Helens. In addition, we present comprehensive bulk-rock geochemistry for a time-series of representative (2004?7) eruption products. This data, along with that in a companion report on Mount St. Helens 2004 to 2006 tephra by Rowe and others (2008), are presented in support of the contents of the U.S. Geological Survey Professional Paper 1750 (Sherrod and others, eds., 2008). Readers are referred to appropriate chapters in USGS Professional Paper 1750 for detailed narratives of eruptive activity during this time period and for interpretations of sample characteristics and geochemical data. The suite of rock samples related to the 2004?7 eruption of Mount St. Helens and presented in this catalog are archived at the David A. Johnson Cascades Volcano Observatory, Vancouver, Wash. The Mount St. Helens 2004?7 Dome Sample Catalogue with major- and trace-element geochemistry is tabulated in 3 worksheets of the accompanying Microsoft Excel file, of2008-1130.xls. Table 1 provides location and sampling information. Table 2 presents sample descriptions. In table 3, bulk-rock major and trace-element geochemistry is listed for 44 eruption-related samples with intra-laboratory replicate analyses of 19 dacite lava samples. A brief overview of the collection methods and lithology of dome samples is given below as an aid to deciphering the dome sample catalog. This is followed by an explanation of the categories of sample information (column headers) in Tables 1 and 2. A summary of the analytical methods used to obtain the geochemical data in this report introduces the presentation of major- and trace-element geochemistry of 2004?7 Mount St. Helens dome samples in table 3. Intra-laboratory results for the USGS AGV-2 standard are presented (tables 4 and 5), which demonstrate the compatibility of chemical data from different sources.

Canada's Interagency Volcanic Event Notification Plan: A Work in Progress Since 1990

NASA Astrophysics Data System (ADS)

Hickson, C. J.; Deacon, E.; Erickson, D.; Ilg, H.; Korstad, R.; Miller, E.; Servranckx, R.; White, W.; Whyte, J.

2006-12-01

Canada has had a formal volcanic ash notification network since early 1990. The Interagency Volcanic Event Notification Plan, "IVENP", was created following the near fatal encounter of a 747 passenger aircraft with ash from Mt. Redoubt, Alaska, in December of 1989. The Canadian Airline Pilots Association, brought the matter of aircraft safety and volcanoes to the floor of the Canadian Parliament where it was raised as an issue of significant concern. This concern, coupled with the threat of volcanic ash entering Canadian airspace, not only from Alaskan volcanoes, but also from the Cascade Magmatic Arc to the south (especially Washington and Oregon) and Canada's own history of volcanism, succeeded in generating a call to action. The Minister of Natural Resources Canada called upon his staff to create and maintain a plan. Work on the plan was started immediately and an early version was available to the original eight participating agencies by May 1990. Since that time the plan has been modified a number of times and the response to the three explosive 1992 eruptions of Mt. Spurr, Alaska, provided fertile grounds for testing the links and making modifications. Until 2004, Alaskan and Cascade volcanoes were relatively quiet, but renewed activity at Mt. St. Helens (starting in September of 2004) provided a critical new test of the plan. During the intervening years the plan had been kept current, but was not tested in a real eruption. One of the main challenges has been experienced by changing technology. Reliance on faxing in the 1990s, has been superseded by EMAIL and other electronic means of passing data. However, not all agencies have advanced in their digital capacity equally. The need for 24/7 vigilance and technologies that work under many differing circumstances for different agencies remains paramount. IVENP, if anything, has had to evolve into one which is even more flexible than originally conceived. Maintaining momentum, understanding agency mandates and capabilities, are all important to ensuring a functional effective notification plan resulting in timely action to avoid aircraft-ash confrontation and reducing the impact to people on the ground. Although we have improved various aspects of the plan after 16 years, there are still many things that remain a challenge.

Optimized autonomous space in-situ sensor web for volcano monitoring

USGS Publications Warehouse

Song, W.-Z.; Shirazi, B.; Huang, R.; Xu, M.; Peterson, N.; LaHusen, R.; Pallister, J.; Dzurisin, D.; Moran, S.; Lisowski, M.; Kedar, S.; Chien, S.; Webb, F.; Kiely, A.; Doubleday, J.; Davies, A.; Pieri, D.

2010-01-01

In response to NASA's announced requirement for Earth hazard monitoring sensor-web technology, a multidisciplinary team involving sensor-network experts (Washington State University), space scientists (JPL), and Earth scientists (USGS Cascade Volcano Observatory (CVO)), have developed a prototype of dynamic and scalable hazard monitoring sensor-web and applied it to volcano monitoring. The combined Optimized Autonomous Space In-situ Sensor-web (OASIS) has two-way communication capability between ground and space assets, uses both space and ground data for optimal allocation of limited bandwidth resources on the ground, and uses smart management of competing demands for limited space assets. It also enables scalability and seamless infusion of future space and in-situ assets into the sensor-web. The space and in-situ control components of the system are integrated such that each element is capable of autonomously tasking the other. The ground in-situ was deployed into the craters and around the flanks of Mount St. Helens in July 2009, and linked to the command and control of the Earth Observing One (EO-1) satellite. ?? 2010 IEEE.

Volcanic hazards at Atitlan volcano, Guatemala

USGS Publications Warehouse

Haapala, J.M.; Escobar Wolf, R.; Vallance, James W.; Rose, William I.; Griswold, J.P.; Schilling, S.P.; Ewert, J.W.; Mota, M.

2006-01-01

Atitlan Volcano is in the Guatemalan Highlands, along a west-northwest trending chain of volcanoes parallel to the mid-American trench. The volcano perches on the southern rim of the Atitlan caldera, which contains Lake Atitlan. Since the major caldera-forming eruption 85 thousand years ago (ka), three stratovolcanoes--San Pedro, Toliman, and Atitlan--have formed in and around the caldera. Atitlan is the youngest and most active of the three volcanoes. Atitlan Volcano is a composite volcano, with a steep-sided, symmetrical cone comprising alternating layers of lava flows, volcanic ash, cinders, blocks, and bombs. Eruptions of Atitlan began more than 10 ka [1] and, since the arrival of the Spanish in the mid-1400's, eruptions have occurred in six eruptive clusters (1469, 1505, 1579, 1663, 1717, 1826-1856). Owing to its distance from population centers and the limited written record from 200 to 500 years ago, only an incomplete sample of the volcano's behavior is documented prior to the 1800's. The geologic record provides a more complete sample of the volcano's behavior since the 19th century. Geologic and historical data suggest that the intensity and pattern of activity at Atitlan Volcano is similar to that of Fuego Volcano, 44 km to the east, where active eruptions have been observed throughout the historical period. Because of Atitlan's moderately explosive nature and frequency of eruptions, there is a need for local and regional hazard planning and mitigation efforts. Tourism has flourished in the area; economic pressure has pushed agricultural activity higher up the slopes of Atitlan and closer to the source of possible future volcanic activity. This report summarizes the hazards posed by Atitlan Volcano in the event of renewed activity but does not imply that an eruption is imminent. However, the recognition of potential activity will facilitate hazard and emergency preparedness.

The Volcano Disaster Assistance Program—Helping to save lives worldwide for more than 30 years

USGS Publications Warehouse

Lowenstern, Jacob B.; Ramsey, David W.

2017-10-20

What do you do when a sleeping volcano roars back to life? For more than three decades, countries around the world have called upon the U.S. Geological Survey’s (USGS) Volcano Disaster Assistance Program (VDAP) to contribute expertise and equipment in times of crisis. Co-funded by the USGS and the U.S. Agency for International Development’s Office of U.S. Foreign Disaster Assistance (USAID/OFDA), VDAP has evolved and grown over the years, adding newly developed monitoring technologies, training and exchange programs, and eruption forecasting methodologies to greatly expand global capabilities that mitigate the impacts of volcanic hazards. These advances, in turn, strengthen the ability of the United States to respond to its own volcanic events.VDAP was formed in 1986 in response to the devastating volcanic mudflow triggered by an eruption of Nevado del Ruiz volcano in Colombia. The mudflow destroyed the city of Armero on the night of November 13, 1985, killing more than 25,000 people in the city and surrounding areas. Sadly, the tragedy was avoidable. Better education of the local population and clear communication between scientists and public officials could have allowed warnings to be received, understood, and acted upon prior to the disaster.VDAP strives to ensure that such a tragedy will never happen again. The program’s mission is to assist foreign partners, at their request, in volcano monitoring and empower them to take the lead in mitigating hazards at their country’s threatening volcanoes. Since 1986, team members have responded to over 70 major volcanic crises at more than 50 volcanoes and have strengthened response capacity in 12 countries. The VDAP team consists of approximately 20 geologists, geophysicists, and engineers, who are based out of the USGS Cascades Volcano Observatory in Vancouver, Washington. In 2016, VDAP was a finalist for the Samuel J. Heyman Service to America Medal for its work in improving volcano readiness and warning systems worldwide, helping countries to forecast eruptions, save lives, and reduce economic losses while enhancing America’s ability to respond to domestic volcanic events.

Straddling the tholeiitic/calc-alkaline transition: the effects of modest amounts of water on magmatic differentiation at Newberry Volcano, Oregon

USGS Publications Warehouse

Mandler, Ben E.; Donnelly-Nolan, Julie M.; Grove, Timothy L.

2014-01-01

Melting experiments have been performed at 1 bar (anhydrous) and 1- and 2-kbar H2O-saturated conditions to study the effect of water on the differentiation of a basaltic andesite. The starting material was a mafic pumice from the compositionally zoned tuff deposited during the ~75 ka caldera-forming eruption of Newberry Volcano, a rear-arc volcanic center in the central Oregon Cascades. Pumices in the tuff of Newberry caldera (TNC) span a continuous silica range from 53 to 74 wt% and feature an unusually high-Na2O content of 6.5 wt% at 67 wt% SiO2. This wide range of magmatic compositions erupted in a single event makes the TNC an excellent natural laboratory in which to study the conditions of magmatic differentiation. Our experimental results and mineral–melt hygrometers/thermometers yield similar estimates of pre-eruptive H2O contents and temperatures of the TNC liquids. The most primitive (mafic) basaltic andesites record a pre-eruptive H2O content of 1.5 wt% and a liquidus temperature of 1,060–1,070 °C at upper crustal pressure. This modest H2O content produces a distinctive fractionation trend that is much more enriched in Na, Fe, and Ti than the calc-alkaline trend typical of wetter arc magmas, but slightly less enriched in Fe and Ti than the tholeiitic trend of dry magmas. Modest H2O contents might be expected at Newberry Volcano given its location in the Cascade rear arc, and the same fractionation trend is also observed in the rim andesites of the rear-arc Medicine Lake volcano in the southern Cascades. However, the Na–Fe–Ti enrichment characteristic of modest H2O (1–2 wt%) is also observed to the west of Newberry in magmas erupted from the arc axis, such as the Shevlin Park Tuff and several lava flows from the Three Sisters. This shows that modest-H2O magmas are being generated directly beneath the arc axis as well as in the rear arc. Because liquid lines of descent are particularly sensitive to water content in the range of 0–3 wt% H2O, they provide a quantitative and reliable tool for precisely determining pre-eruptive H2O content using major-element data from pumices or lava flows. Coupled enrichment in Na, Fe, and Ti relative to the calc-alkaline trend is a general feature of fractional crystallization in the presence of modest amounts of H2O, which may be used to look for “damp” fractionation sequences elsewhere.

Application of the Landsat Thematic Mapper to the identification of potentially active volcanoes in the Central Andes

NASA Technical Reports Server (NTRS)

Francis, P. W.; De Silva, S. L.

1989-01-01

A systematic study of the potentially active volcanoes in the Central Andes (14 deg S to 28 deg S) was carried out on the basis of Landsat Thematic Mapper images which provided consistent coverage of the area. More than 60 major volcanoes were identified as potentially active, as compared to 16 that are listed in the Catalog of Active Volcanoes of the World (Casertano, 1963; Hantke and Parodi, 1966). Most of these volcanoes are large (up to 6000 m in height) composite cones. Some of them could threaten nearby settlements, especially those in southern Peru, where the volcanoes rise above deep canyons with settlements along them.

Scrubbing masks magmatic degassing during repose at Cascade-Range and Aleutian-Arc volcanoes

USGS Publications Warehouse

Symonds, Robert B.; Janik, C.J.; Evans, William C.; Ritchie, B.E.; Counce, Dale; Poreda, R.J.; Iven, Mark

2003-01-01

Between 1992 and 1998, we sampled gas discharges from ≤173°C fumaroles and springs at 12 quiescent but potentially restless volcanoes in the Cascade Range and Aleutian Arc (CRAA) including Mount Shasta, Mount Hood, Mount St. Helens, Mount Rainier, Mount Baker, Augustine Volcano, Mount Griggs, Trident, Mount Mageik, Aniakchak Crater, Akutan, and Makushin. For each site, we collected and analyzed samples to characterize the chemical (H2O, CO2, H2S, N2, CH4, H2, HCl, HF, NH3, Ar, O2, He) and isotopic (δ13C of CO2, 3He/4He, 40Ar/36Ar, δ34S, δ13C of CH4, δ15N, and δD and δ18O of water) compositions of the gas discharges, and to create baseline data for comparison during future unrest. The chemical and isotopic data show that these gases contain a magmatic component that is heavily modified from scrubbing by deep hydrothermal (150° - 350°C) water (primary scrubbing) and shallow meteoric water (secondary scrubbing). The impact of scrubbing is most pronounced in gas discharges from bubbling springs; gases from boiling-point fumaroles and superheated vents show progressively less impact from scrubbing. The most effective strategies for detecting gas precursors to future CRAA eruptions are to measure periodically the emission rates of CO2 and SO2, which have low and high respective solubilities in water, and to monitor continuously CO2 concentrations in soils around volcanic vents. Timely resampling of fumaroles can augment the geochemical surveillance program by watching for chemical changes associated with drying of fumarolic pathways (all CRAA sites), increases in gas geothermometry temperatures (Mount Mageik, Trident, Mount Baker, Mount Shasta), changes in δ13C of CO2 affiliated with magma movement (all CRAA site), and increases in 3He/4He coupled with intrusion of new magma (Mount Rainier, Augustine Volcano, Makushin, Mount Shasta). Repose magmatic degassing may discharge substantial amounts of S and Cl into the edifices of Mount Baker and several other CRAA volcanoes that is trapped by primary and secondary scrubbing. The consequent acidic fluids produce ongoing alteration in the 0.2- to 3-km-deep hydrothermal systems and in fields of boiling-point fumaroles near the surface. Such alteration may influence edifice stability and contribute to the formation of more-hazardous cohesive debris flows. In particular, we recommend further investigation of the volume, extent, and hazards of hydrothermal alteration at Mount Baker. Other potential hazards associated with the CRAA volcano hydrothermal systems include hydrothermal eruptions and, for deeper systems intruded by magma, deep-seated edifice collapse.

Earth observations taken from orbiter Discovery during STS-85 mission

NASA Image and Video Library

1997-08-11

STS085-716-081 (7-19 August 1997) --- This photograph provides a southerly view from Vancouver, B. C. in the foreground, to Portland, Oregon near the top. Coastal stratus, a common occurrence, hugs the Pacific coastline and laps into Puget sound. The silty Fraser River cuts through Vancouver and empties into Puget Sound with a large, milky plume of sediment (bottom). Near the top of the image, the Columbia River runs across the Cascades (between Mt. Adams and Mt. Hood) and the Coast Ranges to the Pacific Ocean. Snow caps the highest peaks of the Olympic Mountains (near center), and the Cascade volcanoes of Rainier (closest to Seattle), Adams and Hood (top). The smaller, gray mountain just south (above and right) of Rainier is Mt. St. Helens.

Living on Active Volcanoes - The Island of Hawai'i

USGS Publications Warehouse

Heliker, Christina; Stauffer, Peter H.; Hendley, James W.

1997-01-01

People on the Island of Hawai'i face many hazards that come with living on or near active volcanoes. These include lava flows, explosive eruptions, volcanic smog, damaging earthquakes, and tsunamis (giant seawaves). As the population of the island grows, the task of reducing the risk from volcano hazards becomes increasingly difficult. To help protect lives and property, U.S. Geological Survey (USGS) scientists at the Hawaiian Volcano Observatory closely monitor and study Hawai'i's volcanoes and issue timely warnings of hazardous activity.

Acoustic Flow Monitor System - User Manual

USGS Publications Warehouse

LaHusen, Richard

2005-01-01

INTRODUCTION The Acoustic Flow Monitor (AFM) is a portable system that was designed by the U.S. Geological Survey Cascades Volcano Observatory to detect and monitor debris flows associated with volcanoes. It has been successfully used internationally as part of real-time warning systems in valleys threatened by such flows (Brantley, 1990; Marcial and others, 1996; Lavigne and others, 2000). The AFM system has also been proven to be an effective tool for monitoring some non-volcanic debris flows. This manual is intended to serve as a basic guide for the installation, testing, and maintenance of AFM systems. An overview of how the system works, as well as instructions for installation and guidelines for testing, is included. Interpretation of data is not covered in this manual; rather, the user should refer to the references provided for published examples of AFM data.

Kamchatka and North Kurile Volcano Explosive Eruptions in 2015 and Danger to Aviation

NASA Astrophysics Data System (ADS)

Girina, Olga; Melnikov, Dmitry; Manevich, Alexander; Demyanchuk, Yury; Nuzhdaev, Anton; Petrova, Elena

2016-04-01

There are 36 active volcanoes in the Kamchatka and North Kurile, and several of them are continuously active. In 2015, four of the Kamchatkan volcanoes (Sheveluch, Klyuchevskoy, Karymsky and Zhupanovsky) and two volcanoes of North Kurile (Alaid and Chikurachki) had strong and moderate explosive eruptions. Moderate gas-steam activity was observing of Bezymianny, Kizimen, Avachinsky, Koryaksky, Gorely, Mutnovsky and other volcanoes. Strong explosive eruptions of volcanoes are the most dangerous for aircraft because they can produce in a few hours or days to the atmosphere and the stratosphere till several cubic kilometers of volcanic ash and aerosols. Ash plumes and the clouds, depending on the power of the eruption, the strength and wind speed, can travel thousands of kilometers from the volcano for several days, remaining hazardous to aircraft, as the melting temperature of small particles of ash below the operating temperature of jet engines. The eruptive activity of Sheveluch volcano began since 1980 (growth of the lava dome) and is continuing at present. Strong explosive events of the volcano occurred in 2015: on 07, 12, and 15 January, 01, 17, and 28 February, 04, 08, 16, 21-22, and 26 March, 07 and 12 April: ash plumes rose up to 7-12 km a.s.l. and extended more 900 km to the different directions of the volcano. Ashfalls occurred at Ust'-Kamchatsk on 16 March, and Klyuchi on 30 October. Strong and moderate hot avalanches from the lava dome were observing more often in the second half of the year. Aviation color code of Sheveluch was Orange during the year. Activity of the volcano was dangerous to international and local aviation. Explosive-effusive eruption of Klyuchevskoy volcano lasted from 01 January till 24 March. Strombolian explosive volcanic activity began from 01 January, and on 08-09 January a lava flow was detected at the Apakhonchich chute on the southeastern flank of the volcano. Vulcanian activity of the volcano began from 10 January. Ashfalls occurred on 11 and 28 January, and 07 February at Kozyrevsk; and on 21 and 27 January, 05, 11, and 13-16 February at Klyuchi. Paroxysmal phase of the eruption displayed on 15 February: explosions sent ash up to 8 km a.s.l. during five hours, ash plumes drifted for about 1000 km mainly to the eastern directions of the volcano. A thermal anomaly began to noting at satellite images again from 28 August; and it was registering time to time till 31 December. Aviation color code of the volcano was Yellow on 01-11 January; Orange from 11 January to 15 February; Red on 15 February; Orange from 15 February to 25 March; Yellow from 25 March till 06 April; Green on 06-14 April; Yellow on 14-18 April; Orange on 18-26 April; Yellow from 26 April to 05 May; Orange on 05-13 May; Yellow from 13 May to 20 July; Green from 20 July to 28 August; Yellow from 28 August to 31 December. Activity of the volcano was dangerous to international and local aviation. Karymsky volcano has been in a state of explosive eruption since 1996. The moderate ash explosions of this volcano were noting during the year, ash plumes rose up to 5 km a.s.l. and extended more 300 km mainly to the eastern directions of the volcano. Aviation color code of the volcano was Orange during the year. Activity of the volcano was dangerous to local aviation. Explosive eruption of Zhupanovsky volcano began on 06 June, 2014, and finished 30 November, 2015. Explosions sent ash up to 8-11 km a.s.l. on 07-08 and 25 March, 12 July, and 30 November; and in the other days - up to 3.5-6 km a.s.l. Ash plumes extended for about 1200 km mainly to the eastern directions of the volcano. In the periods from 26 January to 06 February, 09-15 February, 23 February - 01 March, from 25 March to 03 April, from 04 April to 20 May, from 21 May to 08 June, from 16 June to 12 July, from 15 July to 27 November, the volcano was in a state of relative calm. The culminations of the 2014-2015 eruption of the volcano were explosions and collapses of parts of Priemysh active cone on 12 and 14 July, and 30 November, 2015. Aviation color code of the volcano was Orange from 01 January to 16 May; Yellow from 16 May to 08 June; Orange from 08 June to 19 July; Yellow on 19-20 July; Green from 20 July to 27 November; Orange from 27 November to 10 December; Yellow on 10-17 December; and Green on 17-31 December. Activity of the volcano was dangerous to international and local aviation. The eruptive activity of Chikurachki volcano lasted on 15-19 February. First explosions sent ash up to 7.5 km a.s.l., but later ash plumes drifted on the height about 3-4 km a.s.l. from the volcano. Aviation color code of the volcano was Orange during 16-22 February, and Yellow on 22-26 February. Activity of the volcano was dangerous to local aviation. The intensive thermal anomaly over Alaid volcano was detecting at satellite images from 01 October till 31 December. Aviation color code of the volcano was Yellow during this time. A strong gas-steam activity of the volcano sometimes was observing. Activity of the volcano was dangerous to local aviation.

A model for the magmatic-hydrothermal system at Mount Rainier, Washington, from seismic and geochemical observations

USGS Publications Warehouse

Moran, S.C.; Zimbelman, D.R.; Malone, S.D.

2000-01-01

Mount Rainier is one of the most seismically active volcanoes in the Cascade Range, with an average of one to two high-frequency volcano-tectonic (or VT) earthquakes occurring directly beneath the summit in a given month. Despite this level of seismicity, little is known about its cause. The VT earthquakes occur at a steady rate in several clusters below the inferred base of the Quaternary volcanic edifice. More than half of 18 focal mechanisms determined for these events are normal, and most stress axes deviate significantly from the regional stress field. We argue that these characteristics are most consistent with earthquakes in response to processes associated with circulation of fluids and magmatic gases within and below the base of the edifice. Circulation of these fluids and gases has weakened rock and reduced effective stress to the point that gravity-induced brittle fracture, due to the weight of the overlying edifice, can occur. Results from seismic tomography and rock, water, and gas geochemistry studies support this interpretation. We combine constraints from these studies into a model for the magmatic system that includes a large volume of hot rock (temperatures greater than the brittle-ductile transition) with small pockets of melt and/or hot fluids at depths of 8-18 km below the summit. We infer that fluids and heat from this volume reach the edifice via a narrow conduit, resulting in fumarolic activity at the summit, hydrothermal alteration of the edifice, and seismicity.

Crisis GIS: Preparing for the Next Volcanic Crisis in the United States

NASA Astrophysics Data System (ADS)

Ramsey, D. W.; Robinson, J. E.; Schilling, S. P.; Schaefer, J. R.; Kimberly, P.; Trusdell, F. A.; Guffanti, M. C.; Mayberry, G. C.; Cameron, C. E.; Smith, J. G.; McIntire, J. A.; Snedigar, S.; Ewert, J. W.

2004-12-01

Geographic Information Systems (GIS) specialists from the Volcano Hazards Program (VHP) of the U.S. Geological Survey (USGS), including personnel at Menlo Park, California, the Cascades Volcano Observatory in Vancouver, Washington, the Alaska Volcano Observatory in Anchorage and Fairbanks, Alaska, the Hawaiian Volcano Observatory in Hawaii National Park, Hawaii, and the Smithsonian Institution Global Volcanism Program in Washington, DC, are developing a GIS response plan in the event of a volcano crisis. This plan, referred to as "Crisis GIS", outlines how VHP can ensure rapid, reliable delivery of spatial and ancillary information for data analysis and visualization at any required location during a volcanic crisis or event within the United States. An effective Crisis GIS needs the capacity to store multiple, large datasets, including: base layer data, elevation data, geologic maps, hazard assessment maps, satellite data, and aerial photography for volcanoes around the U.S. It must be readily accessible by VHP GIS specialists stationed around the Nation. Such a GIS should also support installations of monitoring instruments and telemetry equipment that relay monitoring signals, and provision of updates to public officials, the media, and the public during a crisis. GIS technology has proven to be an invaluable tool for crisis response. Recently, GIS was applied as part of the response efforts to two large-scale crises: the terrorist attacks of September 11, 2001, and the Southern California wildfires of Fall 2003. In each case, GIS was used to organize large quantities of spatial data and to produce electronic and paper maps that illustrated hazards, supported decision making, and communicated developing situations to responsible emergency-management authorities and to the populace affected (Kant, 2002, and Pratt, 2003). VHP GIS specialists are currently testing the software and hardware employed in recent major crisis response efforts and are learning to adapt the technology for volcano crisis response.

The STRATegy COLUMN for Precollege Science Teachers: Volcanic Activity.

ERIC Educational Resources Information Center

Metzger, Ellen Pletcher

1995-01-01

Describes resources for information and activities involving volcanoes. Includes an activity that helps students become familiar with the principal types of volcanoes and explores how the viscosity of magma affects the way a volcano erupts. (MKR)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yokoyama, I.

One may assume a center of volcanic activities beneath the edifice of an active volcano, which is here called the focus of the volcano. Sometimes it may be a ''magma reservoir''. Its depth may differ with types of magma and change with time. In this paper, foci of volcanoes are discussed from the viewpoints of four items: (1) Geomagnetic changes related with volcanic activities; (2) Crustal deformations related with volcanic activities; (3) Magma transfer through volcanoes; and (4) Subsurface structure of calderas.

Human Impact on the Geomorphological Evolution of the Opak River Following the 2010 Large Volcanic Event of the Merapi (Indonesia)

NASA Astrophysics Data System (ADS)

Gob, F.; Gautier, E.; Virmoux, C.; Grancher, D.; Tamisier, V.; Primanda, K. W.; Wibowo, S. B.

2016-12-01

During large eruptions, active volcanos may introduce very large quantities of sediment to the drainage system through tephra falls and pyroclastic flows, thus modifying the river system. Once remobilized, the sediment inputs propagate downstream as a sediment wave modifying the channel geometry of the river and reloading the sediment cascade of the catchments. Considering the extreme nature of the volcanic events, the parameters that control the post-eruption evolution of the river system are generally only described as natural and the role played by human activities seems negligible. Communities that live on the volcano slopes and foothills are rather considered to suffer from natural disasters associated with the eruption and its consequences (lahars, etc.) or take advantage of the benefits of the volcanic environment (rich soil, mining and geothermal resources, etc.). This study examines the impact of human influence on the fluvial readjustment of a Javanese river impacted by a major eruption of the Merapi volcano (Indonesia) in October/November 2010. The basin of the Opak River was subject to substantial sediment input related to massive pyroclastic deposits that were remobilized by numerous lahars during the year after the eruption. Two study sites were equipped in order to evaluate the morphodynamic evolution of the riverbed of the Opak River. Topographic surveys, bedload particle marking and suspended sediment sampling revealed an important sediment mobilization during efficient flash-floods. Surprisingly, no bed aggradation related to the progradation of a sediment wave was observed. Two years after the eruptive event, marked bed incision was observed. The Opak River readjustment differs from that of other fluvial systems affected by massive eruptions in two ways. Firstly, the local population massively extracted the sand and blocks injected by the eruption as they represent a valuable economic resource. Secondly, several dams trapped the major part of the sediment load remobilized by lahars.

Critical and supercritical flows in two unstable, mountain rivers, Toutle river system, Washington

USGS Publications Warehouse

Simon, Andrew; Hardison, J. H.

1994-01-01

Critical and supercritical flows are generally considered to be rare occurrences in natural river channels. This paper presents data and results pertaining to the existence of measured critical and supercritical flows at gaging stations on the North Fork Toutle River (NFT) and Toutle River main stem (TR). The data set includes 930 discharge measurements made by the staff of the U.S. Geological Survey, Cascades Volcano Observatory, between 1980 and 1989.

Volcanoes: Nature's Caldrons Challenge Geochemists.

ERIC Educational Resources Information Center

Zurer, Pamela S.

1984-01-01

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

Alaska Volcano Observatory

USGS Publications Warehouse

Venezky, Dina Y.; Murray, Tom; Read, Cyrus

2008-01-01

Steam plume from the 2006 eruption of Augustine volcano in Cook Inlet, Alaska. Explosive ash-producing eruptions from Alaska's 40+ historically active volcanoes pose hazards to aviation, including commercial aircraft flying the busy North Pacific routes between North America and Asia. The Alaska Volcano Observatory (AVO) monitors these volcanoes to provide forecasts of eruptive activity. AVO is a joint program of the U.S. Geological Survey (USGS), the Geophysical Institute of the University of Alaska Fairbanks (UAFGI), and the State of Alaska Division of Geological and Geophysical Surveys (ADGGS). AVO is one of five USGS Volcano Hazards Program observatories that monitor U.S. volcanoes for science and public safety. Learn more about Augustine volcano and AVO at http://www.avo.alaska.edu.

Ubinas Volcano Activity in Peruvian Andes

NASA Image and Video Library

2014-05-01

On April 28, 2014, NASA Terra spacecraft spotted signs of activity at Ubinas volcano in the Peruvian Andes. The appearance of a new lava dome in March 2014 and frequent ash emissions are signs of increasing activity at this volcano.

Coupling at Mauna Loa and Kīlauea by stress transfer in an asthenospheric melt layer

USGS Publications Warehouse

Gonnermann, Helge M.; Foster, James H.; Poland, Michael; Wolfe, Cecily J.; Brooks, Benjamin A.; Miklius, Asta

2012-01-01

The eruptive activity at the neighbouring Hawaiian volcanoes, Kīlauea and Mauna Loa, is thought to be linked despite both having separate lithospheric magmatic plumbing systems. Over the past century, activity at the two volcanoes has been anti-correlated, which could reflect a competition for the same magma supply. Yet, during the past decade Kīlauea and Mauna Loa have inflated simultaneously. Linked activity between adjacent volcanoes in general remains controversial. Here we present a numerical model for the dynamical interaction between Kīlauea and Mauna Loa, where both volcanoes are coupled by pore-pressure diffusion, occurring within a common, asthenospheric magma supply system. The model is constrained by measurements of gas emission rates indicative of eruptive activity, and it is calibrated to match geodetic measurements of surface deformation at both volcanoes, inferred to reflect changes in shallow magma storage. Although an increase in the asthenospheric magma supply can cause simultaneous inflation of Kīlauea and Mauna Loa, we find that eruptive activity at one volcano may inhibit eruptions of the adjacent volcano, if there is no concurrent increase in magma supply. We conclude that dynamic stress transfer by asthenospheric pore pressure is a viable mechanism for volcano coupling at Hawai‘i, and perhaps for adjacent volcanoes elsewhere.

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

USGS Publications Warehouse

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.

Deep structure of Medicine Lake volcano, California

USGS Publications Warehouse

Ritter, J.R.R.; Evans, J.R.

1997-01-01

Medicine Lake volcano (MLV) in northeastern California is the largest-volume volcano in the Cascade Range. The upper-crustal structure of this Quaternary shield volcano is well known from previous geological and geophysical investigations. In 1981, the U.S. Geological Survey conducted a teleseismic tomography experiment on MLV to explore its deeper structure. The images we present, calculated using a modern form of the ACH-inversion method, reveal that there is presently no hint of a large (> 100 km3), hot magma reservoir in the crust. The compressional-wave velocity perturbations show that directly beneath MLV's caldera there is a zone of increased seismic velocity. The perturbation amplitude is +10% in the upper crust, +5% in the lower crust, and +3% in the lithospheric mantle. This positive seismic velocity anomaly presumably is caused by mostly subsolidus gabbroic intrusive rocks in the crust. Heat and melt removal are suggested as the cause in the upper mantle beneath MLV, inferred from petro-physical modeling. The increased seismic velocity appears to be nearly continuous to 120 km depth and is a hint that the original melts come at least partly from the lower lithospheric mantle. Our second major finding is that the upper mantle southeast of MLV is characterized by relatively slow seismic velocities (-1%) compared to the northwest side. This anomaly is interpreted to result from the elevated temperatures under the northwest Basin and Range Province.

SmallWorld Behavior of the Worldwide Active Volcanoes Network: Preliminary Results

NASA Astrophysics Data System (ADS)

Spata, A.; Bonforte, A.; Nunnari, G.; Puglisi, G.

2009-12-01

We propose a preliminary complex networks based approach in order to model and characterize volcanoes activity correlation observed on a planetary scale over the last two thousand years. Worldwide volcanic activity is in fact related to the general plate tectonics that locally drives the faults activity, that in turn controls the magma upraise beneath the volcanoes. To find correlations among different volcanoes could indicate a common underlying mechanism driving their activity and could help us interpreting the deeper common dynamics controlling their unrest. All the first evidences found testing the procedure, suggest the suitability of this analysis to investigate global volcanism related to plate tectonics. The first correlations found, in fact, indicate that an underlying common large-scale dynamics seems to drive volcanic activity at least around the Pacific plate, where it collides and subduces beneath American, Eurasian and Australian plates. From this still preliminary analysis, also more complex relationships among volcanoes lying on different tectonic margins have been found, suggesting some more complex interrelationships between different plates. The understanding of eventually detected correlations could be also used to further implement warning systems, relating the unrest probabilities of a specific volcano also to the ongoing activity to the correlated ones. Our preliminary results suggest that, as for other many physical and biological systems, an underlying organizing principle of planetary volcanoes activity might exist and it could be a small-world principle. In fact we found that, from a topological perspective, volcanoes correlations are characterized by the typical features of small-world network: a high clustering coefficient and a low characteristic path length. These features confirm that global volcanoes activity is characterized by both short and long-range correlations. We stress here the fact that numerical simulation carried out in this work seems to agree with geological evidences (eg. the Pacific plate, South America volcanoes activity and so on). However a detailed analysis of numerical correlation pointed out in this work and geological implication requires a lot of effort and is still running. Thus this work represents preliminary contribution to better understand and clarify, from a geophysical point of view, the nature of planetary correlations among active volcanoes. Further work is still needed.

Volcanoes

MedlinePlus

... Oregon have the most active volcanoes, but other states and territories have active volcanoes, too. A volcanic eruption may involve lava and other debris that can flow up to 100 mph, destroying everything in their ...

Modeled inundation limits of potential lahars from Mount Adams in the White Salmon River Valley, Washington

USGS Publications Warehouse

Griswold, Julia P.; Pierson, Thomas C.; Bard, Joseph A.

2018-05-09

Lahars large enough to reach populated areas are a hazard at Mount Adams, a massive volcano in the southern Cascade Range of Washington State (fig. 1). It is considered to be still active and has the potential to erupt again. By definition, lahars are gravity-driven flows of water-saturated mixtures of mud and rock (plus or minus ice, wood, and other debris), which originate from volcanoes and have a variety of potential triggering mechanisms (Vallance, 2000; Vallance and Iverson, 2015). Flowing mixtures can range in fluid consistency from something like a milkshake to something more like wet concrete, and they behave like flash floods, in that they can appear suddenly in river channels with little warning and commonly have boulder- or log-choked flow fronts. Lahars are hazardous because they can flow rapidly in confined valleys (commonly 20–35 miles per hour [mph] or 9–16 meters per second [m/s]), can travel more than 100 miles (mi) (161 kilometers [km]) from a source volcano, and can move with incredible destructive force, carrying multi-ton boulders and logs that can act as battering rams (Pierson, 1998). The biggest threats from lahars to downstream communities are present during eruptive activity, and impacts to communities can be dire. For example, a very large eruption-triggered lahar in Colombia in 1985 surprised and killed more than 20,000 people in a large town located about 45 mi (72 km) downstream and out of sight of the volcano that produced it (Pierson and others, 1990).Mount Adams, one of the largest volcanoes in the Cascade Range, is a composite stratocone composed primarily of andesite lava flows. It has been the most continuously active volcano within the 480-mi2 Mount Adams volcanic field—a region covering parts of Klickitat, Skamania, Yakima, andLewis Counties and part of the Yakama Nation Reservation in Washington State (Hildreth and Fierstein,1995, 1997). About 500,000 years in age, Mount Adams reached its present size by about 15,000 years ago, primarily through the episodic effusion of lava flows; it has not had a history of major explosive eruptions like Mount St. Helens, its neighbor to the west. Timing of the most recent eruptive activity (recorded by four thin tephra layers) is on the order of 1,000 years ago; the tephras are bracketed by 2,500-year-old and 500-year-old ash layers from Mount St. Helens (Hildreth and Fierstein, 1995, 1997). Mount Adams currently shows no signs of renewed unrest.Eruptive history does not tell us everything we need to know about hazards at Mount Adams, however, which are fully addressed in the volcano hazard assessment for Mount Adams (W.E. Scott and others, 1995). This volcano has had a long-active hydrothermal system that circulated acidic hydrothermal fluids, formed by the solution of volcanic gases in heated groundwater, through fractures and permeable zones into upper parts of the volcanic cone. Acid sulfate leaching of rocks in the summit area may still be occurring, but chemical and thermal evidence suggests that the main hydrothermal system is no longer active at Mount Adams (Nathenson and Mariner, 2013). However, these rock-weakening chemical reactions have operated long enough to change about 0.4 cubic miles (mi3) (1.7 cubic kilometers [km3]) of the hard lava rock in the volcano’s upper cone to a much weaker clay-rich rock, thus significantly reducing rock strength and thereby slope stability in parts of the cone (Finn and others, 2007). The two largest previous lahars from Mount Adams were triggered by landslides of hydrothermally altered rock from the upper southwestern flank of the cone, and any future large lahars are likely to be triggered by the same mechanism. Mount Rainier also has had extensive hydrothermal alteration of rock in its upper edifice, and it also has a history of large landslides that transform into lahars (K.M. Scott and others, 1995; Vallance and Scott, 1997; Reid and others, 2001).The spatial depiction of modeled lahar inundation zones accompanying this report, shown in two different map perspectives, is intended to augment (not replace) the existing hazard maps for Mount Adams (W.E. Scott and others, 1995; Vallance, 1999). The maps in this report show potential areas of inundation by lahars of different initial volumes, which are determined by a computer model, LAHARZ (Iverson and others, 1998; Schilling, 1998). One map sheet presents LAHARZ-determined inundation areas on a normal plan-view shaded-relief map of the study area; the other gives an oblique perspective of the landscape with raised topography, as if one were viewing the landscape at an angle from an aircraft (Jenny and Patterson, 2007). LAHARZ was developed after the original hazard maps (based only on mapping of geologic deposits) were made. Predicted inundation zones on these maps provide an alternative approach to estimation of areas that could be inundated as lahars of different volumes pass through the valley. However, there is considerable uncertainty in the exact location of the hazard-zone boundaries shown on these maps, as well as on earlier maps.

A Volcano Exploration Project Pu`u `O`o (VEPP) Exercise: Is Kilauea in Volcanic Unrest? (Invited)

NASA Astrophysics Data System (ADS)

Schwartz, S. Y.

2010-12-01

Volcanic activity captures the interest and imagination of students at all stages in their education. Analysis of real data collected on active volcanoes can further serve to engage students in higher-level inquiry into the complicated physical processes associated with volcanic eruptions. This exercise takes advantage of both student fascination with volcanoes and the recognized benefits of incorporating real, internet-accessible data to achieve its goals of enabling students to: 1) navigate a scientific website; 2) describe the physical events that produce volcano monitoring data; 3) identify patterns in geophysical time-series and distinguish anomalies preceding and synchronous with eruptive events; 4) compare and contrast geophysical time series and 5) integrate diverse data sets to assess the eruptive state of Kilauea volcano. All data come from the VEPP website (vepp.wr.usgs.gov) which provides background information on the historic activity and volcano monitoring methods as well as near-real time volcano monitoring data from the Pu`u `O`o eruptive vent on Kilauea Volcano. This exercise, designed for geology majors, has students initially work individually to acquire basic skills with volcano monitoring data interpretation and then together in a jigsaw activity to unravel the events leading up to and culminating in the July 2007 volcanic episode. Based on patterns established prior to the July 2007 event, students examine real-time volcano monitoring data to evaluate the present activity level of Kilauea volcano. This exercise will be used for the first time in an upper division Geologic Hazards class in fall 2010 and lessons learned including an exercise assessment will be presented.

Size-resolved chemical composition of aerosol emitted by Erebus volcano, Antarctica

NASA Astrophysics Data System (ADS)

Ilyinskaya, E.; Oppenheimer, C.; Mather, T. A.; Martin, R. S.; Kyle, P. R.

2010-03-01

Persistent, open-vent degassing of Erebus volcano, Antarctica, is a significant point source of gases and aerosol to the austral polar troposphere. We report here on the chemical composition and size distribution of the Erebus aerosol, focusing on the water-soluble fraction. The aerosol was sampled at the rim of the active crater using a cascade impactor, which collected and sized particles in 14 size bins from >10 to 0.01 μm. The soluble fraction of the Erebus aerosol is distinct from other volcanic sources in several respects. It is dominated by chloride-bearing particles (over 30% of total mass) and has an unusually high Cl-/SO42- molar ratio of 3.5. Coarse particles contribute little to the total mass of the soluble fraction. Elevated concentrations of F-, Cl-, Br-, and SO42- are found in a narrow particle size fraction of 0.1-0.25 μm. The detection of particulate Br- reinforces our understanding of the potential for quiescent volcanic emissions to deplete tropospheric ozone. The small aerosol size reflects the low atmospheric temperature and humidity, which inhibit particle growth. Halide-alkali metal salts (Na, K)(Cl, F) appear to be the most abundant species in the aerosol. The concentration of Pb is high compared to other volcanoes; its exsolution may be promoted by the high abundance of halogens in Erebus magma. Despite the previously reported high NOx content in the plume, we did not detect significant quantities of nitrate in the near-vent aerosol. Our findings emphasize the potential regional significance of emissions from Erebus for understanding the Antarctic atmospheric composition and glaciochemical records.

Mud volcanoes of the Orinoco Delta, Eastern Venezuela

USGS Publications Warehouse

Aslan, A.; Warne, A.G.; White, W.A.; Guevara, E.H.; Smyth, R.C.; Raney, J.A.; Gibeaut, J.C.

2001-01-01

Mud volcanoes along the northwest margin of the Orinoco Delta are part of a regional belt of soft sediment deformation and diapirism that formed in response to rapid foredeep sedimentation and subsequent tectonic compression along the Caribbean-South American plate boundary. Field studies of five mud volcanoes show that such structures consist of a central mound covered by active and inactive vents. Inactive vents and mud flows are densely vegetated, whereas active vents are sparsely vegetated. Four out of the five mud volcanoes studied are currently active. Orinoco mud flows consist of mud and clayey silt matrix surrounding lithic clasts of varying composition. Preliminary analysis suggests that the mud volcano sediment is derived from underlying Miocene and Pliocene strata. Hydrocarbon seeps are associated with several of the active mud volcanoes. Orinoco mud volcanoes overlie the crest of a mud-diapir-cored anticline located along the axis of the Eastern Venezuelan Basin. Faulting along the flank of the Pedernales mud volcano suggests that fluidized sediment and hydrocarbons migrate to the surface along faults produced by tensional stresses along the crest of the anticline. Orinoco mud volcanoes highlight the proximity of this major delta to an active plate margin and the importance of tectonic influences on its development. Evaluation of the Orinoco Delta mud volcanoes and those elsewhere indicates that these features are important indicators of compressional tectonism along deformation fronts of plate margins. ?? 2001 Elsevier Science B.V. All rights reserved.

Seismic evidence for a cold serpentinized mantle wedge beneath Mount St Helens

PubMed Central

Hansen, S. M.; Schmandt, B.; Levander, A.; Kiser, E.; Vidale, J. E.; Abers, G. A.; Creager, K. C.

2016-01-01

Mount St Helens is the most active volcano within the Cascade arc; however, its location is unusual because it lies 50 km west of the main axis of arc volcanism. Subduction zone thermal models indicate that the down-going slab is decoupled from the overriding mantle wedge beneath the forearc, resulting in a cold mantle wedge that is unlikely to generate melt. Consequently, the forearc location of Mount St Helens raises questions regarding the extent of the cold mantle wedge and the source region of melts that are responsible for volcanism. Here using, high-resolution active-source seismic data, we show that Mount St Helens sits atop a sharp lateral boundary in Moho reflectivity. Weak-to-absent PmP reflections to the west are attributed to serpentinite in the mantle-wedge, which requires a cold hydrated mantle wedge beneath Mount St Helens (<∼700 °C). These results suggest that the melt source region lies east towards Mount Adams. PMID:27802263

Sensor web enables rapid response to volcanic activity

USGS Publications Warehouse

Davies, Ashley G.; Chien, Steve; Wright, Robert; Miklius, Asta; Kyle, Philip R.; Welsh, Matt; Johnson, Jeffrey B.; Tran, Daniel; Schaffer, Steven R.; Sherwood, Robert

2006-01-01

Rapid response to the onset of volcanic activity allows for the early assessment of hazard and risk [Tilling, 1989]. Data from remote volcanoes and volcanoes in countries with poor communication infrastructure can only be obtained via remote sensing [Harris et al., 2000]. By linking notifications of activity from ground-based and spacebased systems, these volcanoes can be monitored when they erupt.Over the last 18 months, NASA's Jet Propulsion Laboratory (JPL) has implemented a Volcano Sensor Web (VSW) in which data from ground-based and space-based sensors that detect current volcanic activity are used to automatically trigger the NASA Earth Observing 1 (EO-1) spacecraft to make highspatial-resolution observations of these volcanoes.

2011 volcanic activity in Alaska: summary of events and response of the Alaska Volcano Observatory

USGS Publications Warehouse

McGimsey, Robert G.; Maharrey, J. Zebulon; Neal, Christina A.

2014-01-01

The Alaska Volcano Observatory (AVO) responded to eruptions, possible eruptions, and volcanic unrest at or near three separate volcanic centers in Alaska during 2011. The year was highlighted by the unrest and eruption of Cleveland Volcano in the central Aleutian Islands. AVO annual summaries no longer report on activity at Russian volcanoes.

Catalog of earthquake hypocenters at Alaskan volcanoes: January 1 through December 31, 2003

USGS Publications Warehouse

Dixon, James P.; Stihler, Scott D.; Power, John A.; Tytgat, Guy; Moran, Seth C.; Sanchez, John J.; McNutt, Stephen R.; Estes, Steve; Paskievitch, John

2004-01-01

The Alaska Volcano Observatory (AVO), a cooperative program of the U.S. Geological Survey, the Geophysical Institute of the University of Alaska Fairbanks, and the Alaska Division of Geological and Geophysical Surveys, has maintained seismic monitoring networks at historically active volcanoes in Alaska since 1988. The primary objectives of this program are the near real time seismic monitoring of active, potentially hazardous, Alaskan volcanoes and the investigation of seismic processes associated with active volcanism. This catalog presents the calculated earthquake hypocenter and phase arrival data, and changes in the seismic monitoring program for the period January 1 through December 31, 2003.The AVO seismograph network was used to monitor the seismic activity at twenty-seven volcanoes within Alaska in 2003. These include Mount Wrangell, Mount Spurr, Redoubt Volcano, Iliamna Volcano, Augustine Volcano, Katmai volcanic cluster (Snowy Mountain, Mount Griggs, Mount Katmai, Novarupta, Trident Volcano, Mount Mageik, Mount Martin), Aniakchak Crater, Mount Veniaminof, Pavlof Volcano, Mount Dutton, Isanotski Peaks, Shishaldin Volcano, Fisher Caldera, Westdahl Peak, Akutan Peak, Makushin Volcano, Okmok Caldera, Great Sitkin Volcano, Kanaga Volcano, Tanaga Volcano, and Mount Gareloi. Monitoring highlights in 2003 include: continuing elevated seismicity at Mount Veniaminof in January-April (volcanic unrest began in August 2002), volcanogenic seismic swarms at Shishaldin Volcano throughout the year, and low-level tremor at Okmok Caldera throughout the year. Instrumentation and data acquisition highlights in 2003 were the installation of subnetworks on Tanaga and Gareloi Islands, the installation of broadband installations on Akutan Volcano and Okmok Caldera, and the establishment of telemetry for the Okmok Caldera subnetwork. AVO located 3911 earthquakes in 2003.This catalog includes: (1) a description of instruments deployed in the field and their locations; (2) a description of earthquake detection, recording, analysis, and data archival systems; (3) a description of velocity models used for earthquake locations; (4) a summary of earthquakes located in 2003; and (5) an accompanying UNIX tar-file with a summary of earthquake origin times, hypocenters, magnitudes, phase arrival times, and location quality statistics; daily station usage statistics; and all HYPOELLIPSE files used to determine the earthquake locations in 2003.

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

USGS Publications Warehouse

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.

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

NASA Astrophysics Data System (ADS)

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 over 60 volcanoes, with an average of 10 volcanoes discussed each week. Notable volcanic activity during November 2000-November 2001 included an eruption beginning on 6 February at Nyamuragira in the Democratic Republic of the Congo; it issued low-viscosity lava flows that traveled towards inhabited towns, and also produced ash clouds that adversely effected the health of residents and livestock near the volcano. Eruptions at Mayon in the Philippines on 24 June and 25 July caused local authorities to raise the alert to the highest level, close area airports, and evacuate thousands of residents near the volcano. Most recently a large flank eruption at Etna in Italy began on 17 July and gained worldwide attention as extensive lava flows threatened a small town and a tourist complex. While the information found in the Weekly Volcanic Activity Report, ranging from large eruptions to small precursory events, is of interest to the general public, it has also proven to be a valuable resource to volcano observatory staff, universities, researchers, secondary schools, and the aviation community.

Geologic framework of the regional ground-water flow system in the Upper Deschutes Basin, Oregon

USGS Publications Warehouse

Lite, Kenneth E.; Gannett, Marshall W.

2002-12-10

Geologic units in the Deschutes Basin were divided into several distinct hydrogeologic units. In some instances the units correspond to existing stratigraphic divisions. In other instances, hydrogeologic units correspond to different facies within a single stratigraphic unit or formation. The hydrogeologic units include Quaternary sediment, deposits of the Cascade Range and Newberry Volcano, four zones within the Deschutes Formation and age-equivalent rocks that roughly correspond with depositional environments, and pre-Deschutes-age strata.

Galileo Near-Infrared Mapping Spectrometer Detects Active Lava Flows at Prometheus Volcano, Io

NASA Image and Video Library

1999-11-04

The active volcano Prometheus on Jupiter moon Io was imaged by NASA Galileo spacecraft during the close flyby of Io on Oct.10, 1999. The spectrometer can detect active volcanoes on Io by measuring their heat in the near-infrared wavelengths.

Explosions within a Deep Crater: Detection from Land and Space

NASA Astrophysics Data System (ADS)

Worden, A. K.; Dehn, J.; De Angelis, S.

2012-12-01

Many volcanoes in the North Pacific exhibit small scale explosive activity. This activity is typified by small explosions throwing ash, blocks, and spatter out of a central vent located within a crater. This material can be thrown out onto the flanks of the volcano if the vent is near enough to the crater rim. However, at some volcanoes, the vent is tens to hundreds of meters below the crater rim. The crater walls constrain the erupted material, causing it to fall back into the vent. Infill of material clogs the vent and can cause future explosions to become muffled. The depth of the crater also inhibits clear views of the vent for satellite remote sensing. In order for a satellite to record an image of a very deep vent, it requires very near vertical pass angle (satellite zenith angle). This viewing geometry is rare, meaning that the majority of images at such volcanoes will show the flanks or the crater walls, not the actual vent or crater floor. A method was developed for using satellite data to monitor the frequency of small explosive activity at numerous volcanoes. By determining the frequency of small explosions seen as thermal features in satellite imagery, a baseline of activity was determined. Any changes from this baseline are then used to indicate possible changes in the volcanic system or eruptive activity of the volcano. This method was used on data collected at Mt. Chuginadak (Cleveland) in Alaska, Karymsky Volcano in Russia, and Stromboli Volcano in Italy with good results. The method was then applied to Shishaldin Volcano in Alaska but was not as useful in determining the activity of the volcano due to the depth of Shishaldin's central crater (400m). This highlights the importance of multi-disciplinary and multi-sensor research to determine the actual activity at a volcano. For this project, explosions at Shishaldin Volcano were counted in both satellite data (thermal anomalies) and seismic data (explosion signals) for a time period from 2008-2010. These datasets are then compared to determine if there is a relationship that can be carried through the data, or if there is any other connecting factor to aid in the detection and monitoring of small scale explosive activity at volcanoes with vents deep within a crater. If a distinguishing factor can be verified by looking at a location with both satellite and seismic monitoring, it may aid in the monitoring of volcanoes where land based monitoring is not safe or financially viable.

The Alaska Volcano Observatory - Expanded Monitoring of Volcanoes Yields Results

USGS Publications Warehouse

Brantley, Steven R.; McGimsey, Robert G.; Neal, Christina A.

2004-01-01

Recent explosive eruptions at some of Alaska's 52 historically active volcanoes have significantly affected air traffic over the North Pacific, as well as Alaska's oil, power, and fishing industries and local communities. Since its founding in the late 1980s, the Alaska Volcano Observatory (AVO) has installed new monitoring networks and used satellite data to track activity at Alaska's volcanoes, providing timely warnings and monitoring of frequent eruptions to the aviation industry and the general public. To minimize impacts from future eruptions, scientists at AVO continue to assess volcano hazards and to expand monitoring networks.

The changing shapes of active volcanoes: History, evolution, and future challenges for volcano geodesy

USGS Publications Warehouse

Poland, Michael P.; Hamburger, Michael W.; Newman, Andrew V.

2006-01-01

At the very heart of volcanology lies the search for the 'plumbing systems' that form the inner workings of Earth’s active volcanoes. By their very nature, however, the magmatic reservoirs and conduits that underlie these active volcanic systems are elusive; mostly they are observable only through circumstantial evidence, using indirect, and often ambiguous, surficial measurements. Of course, we can infer much about these systems from geologic investigation of materials brought to the surface by eruptions and of the exposed roots of ancient volcanoes. But how can we study the magmatic processes that are occurring beneath Earth’s active volcanoes? What are the geometry, scale, physical, and chemical characteristics of magma reservoirs? Can we infer the dynamics of magma transport? Can we use this information to better forecast the future behavior of volcanoes? These questions comprise some of the most fundamental, recurring themes of modern research in volcanology. The field of volcano geodesy is uniquely situated to provide critical observational constraints on these problems. For the past decade, armed with a new array of technological innovations, equipped with powerful computers, and prepared with new analytical tools, volcano geodesists have been poised to make significant advances in our fundamental understanding of the behavior of active volcanic systems. The purpose of this volume is to highlight some of these recent advances, particularly in the collection and interpretation of geodetic data from actively deforming volcanoes. The 18 papers that follow report on new geodetic data that offer valuable insights into eruptive activity and magma transport; they present new models and modeling strategies that have the potential to greatly increase understanding of magmatic, hydrothermal, and volcano-tectonic processes; and they describe innovative techniques for collecting geodetic measurements from remote, poorly accessible, or hazardous volcanoes. To provide a proper context for these studies, we offer a short review of the evolution of volcano geodesy, as well as a case study that highlights recent advances in the field by comparing the geodetic response to recent eruptive episodes at Mount St. Helens. Finally, we point out a few areas that continue to challenge the volcano geodesy community, some of which are addressed by the papers that follow and which undoubtedly will be the focus of future research for years to come.

Thematic mapper studies of Andean volcanoes

NASA Technical Reports Server (NTRS)

Francis, P. W.

1986-01-01

The primary objective was to identify all the active volcanoes in the Andean region of Bolivia. Morphological features of the Tata Sabaya volcano, Bolivia, were studied with the thematic mapper. Details include marginal levees on lava and pyroclastic flows, and summit crater structure. Valley glacier moraine deposits, not easily identified on the multispectral band scanner, were also unambiguous, and provide useful marker horizons on large volcanic edifices which were built up in preglacial times but which were active subsequently. With such high resolution imagery, it is not only possible to identify potentially active volcanoes, but also to use standard photogeological interpretation to outline the history of individual volcanoes.

Klyuchevskaya, Volcano, Kamchatka Peninsula, CIS

NASA Image and Video Library

1991-05-06

STS039-151-179 (28 April-6 May 1991) --- A large format frame of one of the USSR's volcanic complex (Kamchatka area) with the active volcano Klyuchevskaya (Kloo-chevs'-ska-ya), 15,584 feet in elevation. The last reported eruption of the volcano was on April 8, but an ash and steam plume extending to the south was observed by the STS-39 crew almost three weeks later. The south side of the volcano is dirty from the ash fall and landslide activity. The summit is clearly visible, as is the debris flow from an earlier eruption. Just north of the Kamchatka River is Shiveluch, a volcano which was active in early April. There are more than 100 volcanic edifices recognized on Kamchatka, with 15 classified as active.

UAVSAR Acquires False-Color Image of Galeras Volcano, Colombia

NASA Image and Video Library

2013-04-03

This false-color image of Colombia Galeras Volcano, was acquired by UAVSAR on March 13, 2013. A highly active volcano, Galeras features a breached caldera and an active cone that produces numerous small to moderate explosive eruptions.

1997 volcanic activity in Alaska and Kamchatka: summary of events and response of the Alaska Volcano Observatory

USGS Publications Warehouse

McGimsey, Robert G.; Wallace, Kristi L.

1999-01-01

The Alaska Volcano Observatory (AVO) monitors over 40 historically active volcanoes along the Aleutian Arc. Twenty are seismically monitored and for the rest, the AVO monitoring program relies mainly on pilot reports, observations of local residents and ship crews, and daily analysis of satellite images. In 1997, AVO responded to eruptive activity or suspect volcanic activity at 11 volcanic centers: Wrangell, Sanford, Shrub mud volcano, Iliamna, the Katmai group (Martin, Mageik, Snowy, and Kukak volcanoes), Chiginagak, Pavlof, Shishaldin, Okmok, Cleveland, and Amukta. Of these, AVO has real-time, continuously recording seismic networks at Iliamna, the Katmai group, and Pavlof. The phrase “suspect volcanic activity” (SVA), used to characterize several responses, is an eruption report or report of unusual activity that is subsequently determined to be normal or enhanced fumarolic activity, weather-related phenomena, or a non-volcanic event. In addition to responding to eruptive activity at Alaska volcanoes, AVO also disseminated information for the Kamchatkan Volcanic Eruption Response Team (KVERT) about the 1997 activity of 5 Russian volcanoes--Sheveluch, Klyuchevskoy, Bezymianny, Karymsky, and Alaid (SVA). This report summarizes volcanic activity and SVA in Alaska during 1997 and the AVO response, as well as information on the reported activity at the Russian volcanoes. Only those reports or inquiries that resulted in a “significant” investment of staff time and energy (here defined as several hours or more for reaction, tracking, and follow-up) are included. AVO typically receives dozens of reports throughout the year of steaming, unusual cloud sightings, or eruption rumors. Most of these are resolved quickly and are not tabulated here as part of the 1997 response record.

Klyuchevskaya, Volcano, Kamchatka Peninsula, CIS

NASA Technical Reports Server (NTRS)

1991-01-01

Klyuchevskaya, Volcano, Kamchatka Peninsula, CIS (56.0N, 160.5E) is one of several active volcanoes in the CIS and is 15,584 ft. in elevation. Fresh ash fall on the south side of the caldera can be seen as a dirty smudge on the fresh snowfall. Just to the north of the Kamchatka River is Shiveluch, a volcano which had been active a short time previously. There are more than 100 volcanic edifices recognized on Kamchatka, 15 of which are still active.

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

USGS Publications Warehouse

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.

77 FR 16059 - Draft Environmental Impact Statement; Izembek National Wildlife Refuge Land Exchange/Road...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-19

... Aleutian arc chain of volcanoes. Landforms include mountains, active volcanoes, U-shaped valleys, glacial...-foot Shishaldin Volcano. Shishaldin Volcano is a designated National Natural Landmark. Alaska Maritime...

The biogeochemistry of anchialine caves: Progress and possibilities

USGS Publications Warehouse

Pohlman, John W.

2011-01-01

Recent investigations of anchialine caves and sinkholes have identified complex food webs dependent on detrital and, in some cases, chemosynthetically produced organic matter. Chemosynthetic microbes in anchialine systems obtain energy from reduced compounds produced during organic matter degradation (e.g., sulfide, ammonium, and methane), similar to what occurs in deep ocean cold seeps and mud volcanoes, but distinct from dominant processes operating at hydrothermal vents and sulfurous mineral caves where the primary energy source is mantle derived. This review includes case studies from both anchialine and non-anchialine habitats, where evidence for in situ chemosynthetic production of organic matter and its subsequent transfer to higher trophic level metazoans is documented. The energy sources and pathways identified are synthesized to develop conceptual models for elemental cycles and energy cascades that occur within oligotrophic and eutrophic anchialine caves. Strategies and techniques for testing the hypothesis of chemosynthesis as an active process in anchialine caves are also suggested.

Frequency and volumes of ignimbrite eruptions following the Late Neogene initiation of the Central Oregon High Cascades

NASA Astrophysics Data System (ADS)

Pitcher, Bradley W.; Kent, Adam J. R.; Grunder, Anita L.; Duncan, Robert A.

2017-06-01

The late Neogene Deschutes Formation of central Oregon preserves a remarkable volcanic and sedimentary record of the initial stages of High Cascades activity following an eastward shift in the locus of volcanism at 7.5 Ma. Numerous ignimbrite and tephra-fall units are contained within the formation, and since equivalent deposits are relatively rare for the Quaternary Cascades, the eruptions of the earliest High Cascade volcanoes were likely more explosive than those of the Quaternary arc. In this study, the timing and frequency of eruptions which produced 14 laterally extensive marker ignimbrites within the Deschutes Formation are established using 40Ar/39Ar geochronology. Plagioclase 40Ar/39Ar ages for the lowermost (6.25 ± 0.07 Ma) and uppermost (5.45 ± 0.04 Ma) marker ignimbrites indicate that all major explosive eruptions within the Deschutes Formation occurred within a period of 800 ± 54 k.y. (95% confidence interval). Minimum estimates for the volumes of the 14 ignimbrites, using an ArcGIS-based method, range from 1.0 to 9.4 km3 and have a total volume of 62.5 km3. Taken over the 50 km of arc length, the explosive volcanic production rate of the central Oregon High Cascades during Deschutes Formation time was a minimum of 1.8 km3/m.y./km of arc length. By including estimates of the volumes of tephra-fall components, as well as ignimbrites that may have traveled west, we estimate a total volume range, for these 14 eruptions alone, of 188 to 363 km3 ( 121 to 227 km3 DRE), a rate of 4.7-9.1 km3/m.y./km arc length. This explosive volcanic production rate is much higher than the average Quaternary eruption rates, of all compositions, estimated for the entire Cascade arc (1.5-2.5), Alaska Peninsula segment of the Aleutian arc (0.6-1.0), and the Andean southern volcanic zone (1.1-2.0). We suggest that this atypical explosive pulse may result from the onset of regional extension and migration of the magmatic arc, which had the combined effect of increasing magmatic flux and temporarily enhancing melting of more fusible crust.

Mount St. Helens Flyover

NASA Technical Reports Server (NTRS)

2002-01-01

This Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) image of Mt. St. Helens volcano in Washington State was acquired on August 8, 2000 and covers an area of 37 by 51 km. Mount Saint Helens, a volcano in the Cascade Range of southwestern Washington that had been dormant since 1857, began to show signs of renewed activity in early 1980. On 18 May 1980, it erupted with such violence that the top of the mountain was blown off, spewing a cloud of ash and gases that rose to an altitude of 19 kilometers. The blast killed about 60 people and destroyed all life in an area of some 180 square kilometers (some 70 square miles), while a much larger area was covered with ash and debris. It continues to spit forth ash and steam intermittently. As a result of the eruption, the mountain's elevation decreased from 2,950 meters to 2,549 meters. The simulated fly-over was produced by draping ASTER visible and near infrared image data over a digital topography model, created from ASTER's 3-D stereo bands. The color was computer enhanced to create a 'natural' color image, where the vegetation appears green. The topography has been exaggerated 2 times to enhance the appearance of the relief. Landsat7 aquired an image of Mt. St. Helens on August 22, 1999. Image and animation courtesy NASA/GSFC/MITI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team.

Groundwater flow, heat transport, and water table position within volcanic edifices: Implications for volcanic processes in the Cascade Range

USGS Publications Warehouse

Hurwitz, S.; Kipp, K.L.; Ingebritsen, S.E.; Reid, M.E.

2003-01-01

The position of the water table within a volcanic edifice has significant implications for volcano hazards, geothermal energy, and epithermal mineralization. We have modified the HYDROTHERM numerical simulator to allow for a free-surface (water table) upper boundary condition and a wide range of recharge rates, heat input rates, and thermodynamic conditions representative of continental volcano-hydrothermal systems. An extensive set of simulations was performed on a hypothetical stratovolcano system with unconfined groundwater flow. Simulation results suggest that the permeability structure of the volcanic edifice and underlying material is the dominant control on water table elevation and the distribution of pressures, temperatures, and fluid phases at depth. When permeabilities are isotropic, water table elevation decreases with increasing heat flux and increases with increasing recharge, but when permeabilities are anisotropic, these effects can be much less pronounced. Several conditions facilitate the ascent of a hydrothermal plume into a volcanic edifice: a sufficient source of heat and magmatic volatiles at depth, strong buoyancy forces, and a relatively weak topography-driven flow system. Further, the plume must be connected to a deep heat source through a pathway with a time-averaged effective permeability ???1 ?? 10-16 m2, which may be maintained by frequent seismicity. Topography-driven flow may be retarded by low permeability in the edifice and/or the lack of precipitation recharge; in the latter case, the water table may be relatively deep. Simulation results were compared with observations from the Quaternary stratovolcanoes along the Cascade Range of the western United States to infer hydrothermal processes within the edifices. Extensive ice caps on many Cascade Range stratovolcanoes may restrict recharge on the summits and uppermost flanks. Both the simulation results and limited observational data allow for the possibility that the water table beneath the stratovolcanoes is relatively deep.

Earth Observations taken by the Expedition 15 Crew

NASA Image and Video Library

2007-07-10

ISS015-E-16913 (10 July 2007) --- Shiveluch Volcano, Kamchatka, Russian Far East is featured in this image photographed by an Expedition 15 crewmember on the International Space Station. Shiveluch is one of the biggest and most active of a line of volcanoes along the spine of the Kamchatka peninsula in easternmost Russia. In turn the volcanoes and peninsula are part of the tectonically active "Ring of Fire" that almost surrounds the Pacific Ocean, denoted by active volcanoes and frequent earthquakes. Shiveluch occupies the point where the northeast-trending Kamchatka volcanic line intersects the northwest-trending Aleutian volcanic line. Junctions such as this are typically points of intense volcanic activity. According to scientists, the summit rocks of Shiveluch have been dated at approximately 65,000 years old. Lava layers on the sides of the volcano reveal at least 60 major eruptions in the last 10,000 years, making it the most active volcano in the 2,200 kilometer distance that includes the Kamchatka peninsula and the Kuril island chain. Shiveluch rises from almost sea level to well above 3,200 miles (summit altitude 3,283 miles) and is often capped with snow. In this summer image however, the full volcano is visible, actively erupting ash and steam in late June or early July, 2007. The dull brown plume extending from the north of the volcano summit is most likely a combination of ash and steam (top). The two larger white plumes near the summit are dominantly steam, a common adjunct to eruptions, as rain and melted snow percolate down to the hot interior of the volcano. The sides of the volcano show many eroded stream channels. The south slope also reveals a long sloping apron of collapsed material, or pyroclastic flows. Such debris flows have repeatedly slid down and covered the south side of the volcano during major eruptions when the summit lava domes explode and collapse (this occurred during major eruptions in 1854 and 1964). Regrowth of the forest on the south slope (note the contrast with the eastern slope) has been foiled by the combined effects of continued volcanic activity, instability of the debris flows and the short growing season.

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

NASA Astrophysics Data System (ADS)

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

2017-12-01

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

U.S. Geological Survey's Alert Notification System for Volcanic Activity

USGS Publications Warehouse

Gardner, Cynthia A.; Guffanti, Marianne C.

2006-01-01

The United States and its territories have about 170 volcanoes that have been active during the past 10,000 years, and most could erupt again in the future. In the past 500 years, 80 U.S. volcanoes have erupted one or more times. About 50 of these recently active volcanoes are monitored, although not all to the same degree. Through its five volcano observatories, the U.S. Geological Survey (USGS) issues information and warnings to the public about volcanic activity. For clarity of warnings during volcanic crises, the USGS has now standardized the alert-notification system used at its observatories.

Abrupt shift in δ18O values at Medicine Lake volcano (California, USA)

USGS Publications Warehouse

Donnelly-Nolan, J. M.

1998-01-01

 Oxygen-isotope analyses of lavas from Medicine Lake volcano (MLV), in the southern Cascade Range, indicate a significant change in δ18O in Holocene time. In the Pleistocene, basaltic lavas with <52% SiO2 averaged +5.9‰, intermediate lavas averaged +5.7‰, and silicic lavas (≥63.0%SiO2) averaged +5.6‰. No analyzed Pleistocene rhyolites or dacites have values greater than +6.3‰. In post-glacial time, basalts were similar at +5.7‰ to those erupted in the Pleistocene, but intermediate lavas average +6.8‰ and silicic lavas +7.4‰ with some values as high as +8.5‰. The results indicate a change in the magmatic system supplying the volcano. During the Pleistocene, silicic lavas resulted either from melting of low-18O crust or from fractionation combined with assimilation of very-low-18O crustal material such as hydrothermally altered rocks similar to those found in drill holes under the center of the volcano. By contrast, Holocene silicic lavas were produced by assimilation and/or wholesale melting of high-18O crustal material such as that represented by inclusions of granite in lavas on the upper flanks of MLV. This sudden shift in assimilant indicates a fundamental change in the magmatic system. Magmas are apparently ponding in the crust at a very different level than in Pleistocene time.

July 1973 ground survey of active Central American volcanoes

NASA Technical Reports Server (NTRS)

Stoiber, R. E. (Principal Investigator); Rose, W. I., Jr.

1973-01-01

The author has identified the following significant results. Ground survey has shown that thermal anomalies of various sizes associated with volcanic activity at several Central American volcanoes should be detectable from Skylab. Anomalously hot areas of especially large size (greater than 500 m in diameter) are now found at Santiaguito and Pacaya volcanoes in Guatemala and San Cristobal in Nicaragua. Smaller anomalous areas are to be found at least seven other volcanoes. This report is completed after ground survey of eleven volcanoes and ground-based radiation thermometry mapping at these same points.

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

NASA Astrophysics Data System (ADS)

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.

Iceland's Grímsvötn volcano erupts

NASA Astrophysics Data System (ADS)

Showstack, Randy

2011-05-01

About 13 months after Iceland's Eyjafjallajökull volcano began erupting on 14 April 2010, which led to extensive air traffic closures over Europe, Grímsvötn volcano in southeastern took its turn. Iceland's most active volcano, which last erupted in 2004 and lies largely beneath the Vatnajökull ice cap, began its eruption activity on 21 May, with the ash plume initially reaching about 20 kilometers in altitude, according to the Icelandic Meteorological Office. Volcanic ash from Grímsvötn has cancelled hundreds of airplane flights and prompted U.S. president Barack Obama to cut short his visit to Ireland. As Eos went to press, activity at the volcano was beginning to subside.

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

USGS Publications Warehouse

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.

Nighttime Look at Ambrym Volcano, Vanuatu by NASA Spacecraft

NASA Image and Video Library

2014-02-12

Ambrym volcano in Vanuatu is one of the most active volcanoes in the world. A large summit caldera contains two active vent complexes, Marum and Benbow is seen in this February 12, 2014 nighttime thermal infrared image from NASA Terra spacecraft.

A Scientific Excursion: Volcanoes.

ERIC Educational Resources Information Center

Olds, Henry, Jr.

1983-01-01

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

Preface

NASA Astrophysics Data System (ADS)

Taran, Yuri; Tassi, Franco; Varekamp, Johan; Inguaggiato, Salvatore; Kalacheva, Elena

2017-10-01

Many volcanoes at any tectonic settings host hydrothermal systems. Volcano-hydrothermal systems (VHS) are result of interaction of the upper part of plumbing systems of active volcanoes with crust, hydrosphere and atmosphere. They are heated by magma, fed by magmatic fluids and meteoric (sea) water, transport and re-distribute magmatic and crustal material. VHS are sensitive to the activity of a host volcano. VHS may have specific features depending on the regional and local tectonic, geologic and geographic settings. The studies reported in this volume help to illustrate the diversity of the approaches and investigations that are being conducting at different volcano-hydrothermal systems over the world and the results of which will be of important value in furthering our understanding of the complex array of the processes accompanying hydrothermal activity of volcanoes. About 60 papers were submitted to a special session of "Volcano-Hydrothermal Systems" at the 2015 fall meeting of the American Geophysical Union. The papers in this special issue of the Journal of Volcanology and Geothermal Research were originally presented at that session.

Low-Cost Photogrammetric Technique Used to Measure Dome Growth at Mount St. Helens Volcano, 2007-2007

NASA Astrophysics Data System (ADS)

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

2007-12-01

We describe a low-cost application of digital photogrammetry using commercial grade software, an off-the-shelf digital camera, a laptop computer and oblique photographs to reconstruct volcanic dome morphology during the on-going eruption at Mount St. Helens, Washington. Renewed activity at Mount St. Helens provides a rare opportunity to devise and test new methods for better understanding and predicting volcanic events, because the new method can be validated against other observations on this well-instrumented volcano. Uncalibrated, oblique aerial photographs (snap shots) taken from a helicopter are the raw data. Twelve sets of overlapping digital images of the dome taken during 2004-2007 were used to produce digital elevation models (DEMs) from which dome height, eruption volume and extrusion rate can be derived. Analyses of the digital images were carried out using PhotoModeler software, which produces three dimensional coordinates of points identified in multiple photos. The steps involved include: (1) calibrating the digital camera using this software package, (2) establishing control points derived from existing DEMs, (3) identifying tie points located in each photo of any given model date, and (4) identifying points in pairs of photos to build a three dimensional model of the evolving dome at each photo date. Text files of three-dimensional points encompassing the dome at each date were imported into ArcGIS and three-dimensional models (triangulated irregular network or TINs) were generated. TINs were then converted to 2 m raster DEMs. The evolving morphology of the growing dome was modeled by comparison of successive DEMs. The volume of extruded lava visible in each DEM was calculated using the 1986 pre-eruption crater floor topography as a basal surface. Results were validated by comparing volume measurements derived from traditional aerophotogrammetric surveys run by the USGS Cascades Volcano Observatory. Our new "quick and cheap" technique yields estimates of eruptive volume consistently within 5% of the volumes estimated with traditional surveys. The end result of this project is a new technique that provides an inexpensive, rapid assessment tool for tracking lava dome growth or other topographic changes at restless volcanoes.

Mantle Helium and Carbon Isotopes in Separation Creek Geothermal Springs, Three Sisters Area, Central Oregon: Evidence for Renewed Volcanic Activity or a Long Term Steady State System?

USGS Publications Warehouse

Van Soest, M. C.; Kennedy, B.M.; Evans, William C.; Mariner, R.H.

2002-01-01

Here we present the helium and carbon isotope results from the initial study of a fluid chemistry-monitoring program started in the summer of 2001 near the South Sister volcano in central Oregon. The Separation Creek area which is several miles due west of the volcano is the locus of strong crustal uplift currently occurring at a rate of 4-5 cm/yr (Wicks, et. al., 2001).Helium [RC/RA = 7.44 and 8.61 RA (RC/R A = (3He/4He)sample-. air corrected/(3He/4He)air))] and carbon (??13C = -11.59 to -9.03??? vs PDB) isotope data and CO2/3He (5 and 9 ?? 109) show that bubbling cold springs in the Separation Creek area near South Sister volcano carry a strong mantle signal, indicating the presence of fresh basaltic magma in the volcanic plumbing system. There is no evidence though, to directly relate this signal to the crustal uplift that is currently taking place in the area, which started in 1998. The geothermal system in the area is apparently much longer lived and shows no significant changes in chemistry compared to data from the early 1990s. Hot springs in the area, which are relatively far removed from the volcanic edifice, do not carry a strong mantle signal in helium isotope ratios (2.79 to 5.08 RA), unlike the cold springs, and also do not show any significant changes in helium isotope ratios compared to literature data for the same springs of over two decades ago. The cold springs of the Separation Creek area form a very diffuse but significant low temperature geothermal system, that should, due to its close vicinity to the center of up uplift, be more sensitive to changes in the deeper volcanic plumbing system than the far removed hot springs and therefore require much more study and consideration when dealing with volcano monitoring in the Cascade range or possibly with geothermal exploration in general.

Optimized Autonomous Space In-situ Sensor-Web for volcano monitoring

USGS Publications Warehouse

Song, W.-Z.; Shirazi, B.; Kedar, S.; Chien, S.; Webb, F.; Tran, D.; Davis, A.; Pieri, D.; LaHusen, R.; Pallister, J.; Dzurisin, D.; Moran, S.; Lisowski, M.

2008-01-01

In response to NASA's announced requirement for Earth hazard monitoring sensor-web technology, a multidisciplinary team involving sensor-network experts (Washington State University), space scientists (JPL), and Earth scientists (USGS Cascade Volcano Observatory (CVO)), is developing a prototype dynamic and scaleable hazard monitoring sensor-web and applying it to volcano monitoring. The combined Optimized Autonomous Space -In-situ Sensor-web (OASIS) will have two-way communication capability between ground and space assets, use both space and ground data for optimal allocation of limited power and bandwidth resources on the ground, and use smart management of competing demands for limited space assets. It will also enable scalability and seamless infusion of future space and in-situ assets into the sensor-web. The prototype will be focused on volcano hazard monitoring at Mount St. Helens, which has been active since October 2004. The system is designed to be flexible and easily configurable for many other applications as well. The primary goals of the project are: 1) integrating complementary space (i.e., Earth Observing One (EO-1) satellite) and in-situ (ground-based) elements into an interactive, autonomous sensor-web; 2) advancing sensor-web power and communication resource management technology; and 3) enabling scalability for seamless infusion of future space and in-situ assets into the sensor-web. To meet these goals, we are developing: 1) a test-bed in-situ array with smart sensor nodes capable of making autonomous data acquisition decisions; 2) efficient self-organization algorithm of sensor-web topology to support efficient data communication and command control; 3) smart bandwidth allocation algorithms in which sensor nodes autonomously determine packet priorities based on mission needs and local bandwidth information in real-time; and 4) remote network management and reprogramming tools. The space and in-situ control components of the system will be integrated such that each element is capable of autonomously tasking the other. Sensor-web data acquisition and dissemination will be accomplished through the use of the Open Geospatial Consortium Sensorweb Enablement protocols. The three-year project will demonstrate end-to-end system performance with the in-situ test-bed at Mount St. Helens and NASA's EO-1 platform. ??2008 IEEE.

75 FR 6215 - Agency Information Collection Activity

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-08

.... SUPPLEMENTARY INFORMATION: I. Abstract During FY10, the Volcano Hazards Program (VHP) will provide funding under the American Recovery and Reinvestment Act (ARRA) for improvement of the volcano and other monitoring systems and other monitoring- related activities that contribute to mitigation of volcano hazards. This...

The 2014 eruptions of Pavlof Volcano, Alaska

USGS Publications Warehouse

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

2017-12-22

Pavlof Volcano is one of the most frequently active volcanoes in the Aleutian Island arc, having erupted more than 40 times since observations were first recorded in the early 1800s . The volcano is located on the Alaska Peninsula (lat 55.4173° N, long 161.8937° W), near Izembek National Wildlife Refuge. The towns and villages closest to the volcano are Cold Bay, Nelson Lagoon, Sand Point, and King Cove, which are all within 90 kilometers (km) of the volcano (fig. 1). Pavlof is a symmetrically shaped stratocone that is 2,518 meters (m) high, and has about 2,300 m of relief. The volcano supports a cover of glacial ice and perennial snow roughly 2 to 4 cubic kilometers (km3) in volume, which is mantled by variable amounts of tephra fall, rockfall debris, and pyroclastic-flow deposits produced during historical eruptions. Typical Pavlof eruptions are characterized by moderate amounts of ash emission, lava fountaining, spatter-fed lava flows, explosions, and the accumulation of unstable mounds of spatter on the upper flanks of the volcano. The accumulation and subsequent collapse of spatter piles on the upper flanks of the volcano creates hot granular avalanches, which erode and melt snow and ice, and thereby generate watery debris-flow and hyperconcentrated-flow lahars. Seismic instruments were first installed on Pavlof Volcano in the early 1970s, and since then eruptive episodes have been better characterized and specific processes have been documented with greater certainty. The application of remote sensing techniques, including the use of infrasound data, has also aided the study of more recent eruptions. Although Pavlof Volcano is located in a remote part of Alaska, it is visible from Cold Bay, Sand Point, and Nelson Lagoon, making distal observations of eruptive activity possible, weather permitting. A busy air-travel corridor that is utilized by a numerous transcontinental and regional air carriers passes near Pavlof Volcano. The frequency of air travel across the region results in a relatively large number of airborne observations of eruptive activity. During the 2014 Pavlof eruptions, the Alaska Volcano Observatory received observations and photographs from pilots and local observers, which aided evaluation of the eruptive activity and the areas affected by eruptive products.This report outlines the chronology of events associated with the 2014 eruptive activity at Pavlof Volcano, provides documentation of the style and character of the eruptive episodes, and reports briefly on the eruptive products and impacts. The principal observations are described and portrayed on maps and photographs, and the 2014 eruptive activity is compared to historical eruptions.

Catalog of earthquake hypocenters at Alaskan volcanoes: January 1, 2000 through December 31, 2001

USGS Publications Warehouse

Dixon, James P.; Stihler, Scott D.; Power, John A.; Tytgat, Guy; Estes, Steve; Moran, Seth C.; Paskievitch, John; McNutt, Stephen R.

2002-01-01

The Alaska Volcano Observatory (AVO), a cooperative program of the U.S. Geological Survey, the Geophysical Institute of the University of Alaska Fairbanks, and the Alaska Division of Geological and Geophysical Surveys, has maintained seismic monitoring networks at potentially active volcanoes in Alaska since 1988 (Power and others, 1993; Jolly and others, 1996; Jolly and others, 2001). The primary objectives of this program are the seismic surveillance of active, potentially hazardous, Alaskan volcanoes and the investigation of seismic processes associated with active volcanism. This catalog reflects the status and evolution of the seismic monitoring program, and presents the basic seismic data for the time period January 1, 2000, through December 31, 2001. For an interpretation of these data and previously recorded data, the reader should refer to several recent articles on volcano related seismicity on Alaskan volcanoes in Appendix G.The AVO seismic network was used to monitor twenty-three volcanoes in real time in 2000-2001. These include Mount Wrangell, Mount Spurr, Redoubt Volcano, Iliamna Volcano, Augustine Volcano, Katmai Volcanic Group (Snowy Mountain, Mount Griggs, Mount Katmai, Novarupta, Trident Volcano, Mount Mageik, Mount Martin), Aniakchak Crater, Pavlof Volcano, Mount Dutton, Isanotski Peaks, Shishaldin Volcano, Fisher Caldera, Westdahl Peak, Akutan Peak, Makushin Volcano, Great Sitkin Volcano, and Kanaga Volcano (Figure 1). AVO located 1551 and 1428 earthquakes in 2000 and 2001, respectively, on and around these volcanoes.Highlights of the catalog period (Table 1) include: volcanogenic seismic swarms at Shishaldin Volcano between January and February 2000 and between May and June 2000; an eruption at Mount Cleveland between February and May 2001; episodes of possible tremor at Makushin Volcano starting March 2001 and continuing through 2001, and two earthquake swarms at Great Sitkin Volcano in 2001.This catalog includes: (1) earthquake origin times, hypocenters, and magnitudes with summary statistics describing the earthquake location quality; (2) a description of instruments deployed in the field and their locations; (3) a description of earthquake detection, recording, analysis, and data archival systems; (4) station parameters and velocity models used for earthquake locations; (5) a summary of daily station usage throughout the catalog period; and (6) all HYPOELLIPSE files used to determine the earthquake locations presented in this report.

Erupting Volcano Mount Etna

NASA Technical Reports Server (NTRS)

2001-01-01

An Expedition Two crewmember aboard the International Space Station (ISS) captured this overhead look at the smoke and ash regurgitated from the erupting volcano Mt. Etna on the island of Sicily, Italy. At an elevation of 10,990 feet (3,350 m), the summit of the Mt. Etna volcano, one of the most active and most studied volcanoes in the world, has been active for a half-million years and has erupted hundreds of times in recorded history.

Using the Landsat Thematic Mapper to detect and monitor active volcanoes - An example from Lascar volcano, northern Chile

NASA Technical Reports Server (NTRS)

Francis, P. W.; Rothery, D. A.

1987-01-01

The Landsat Thematic Mapper (TM) offers a means of detecting and monitoring thermal features of active volcanoes. Using the TM, a prominent thermal anomaly has been discovered on Lascar volcano, northern Chile. Data from two short-wavelength infrared channels of the TM show that material within a 300-m-diameter pit crater was at a temperature of at least 380 C on two dates in 1985. The thermal anomaly closely resembles in size and radiant temperature the anomaly over the active lava lake at Erta'ale in Ethiopia. An eruption took place at Lascar on Sept. 16, 1986. TM data acquired on Oct. 27, 1986, revealed significant changes within the crater area. Lascar is in a much more active state than any other volcano in the central Andes, and for this reason it merits further careful monitoring. Studies show that the TM is capable of confidently identifying thermal anomalies less than 100 m in size, at temperatures of above 150 C, and thus it offers a valuable means of monitoring the conditions of active or potentially active volcanoes, particularly those in remote regions.

Imaging an Active Volcano Edifice at Tenerife Island, Spain

NASA Astrophysics Data System (ADS)

Ibáñez, Jesús M.; Rietbrock, Andreas; García-Yeguas, Araceli

2008-08-01

An active seismic experiment to study the internal structure of Teide volcano is being carried out on Tenerife, a volcanic island in Spain's Canary Islands archipelago. The main objective of the Tomography at Teide Volcano Spain (TOM-TEIDEVS) experiment, begun in January 2007, is to obtain a three-dimensional (3-D) structural image of Teide volcano using seismic tomography and seismic reflection/refraction imaging techniques. At present, knowledge of the deeper structure of Teide and Tenerife is very limited, with proposed structural models based mainly on sparse geophysical and geological data. The multinational experiment-involving institutes from Spain, the United Kingdom, Italy, Ireland, and Mexico-will generate a unique high-resolution structural image of the active volcano edifice and will further our understanding of volcanic processes.

Volcanic activity in Alaska: summary of events and response of the Alaska Volcano Observatory 1993

USGS Publications Warehouse

Neal, Christina A.; McGimsey, Robert G.; Doukas, Michael P.

1996-01-01

During 1993, the Alaska Volcano Observatory (AVO) responded to episodes of eruptive activity or false alarms at nine volcanic centers in the state of Alaska. Additionally, as part of a formal role in KVERT (the Kamchatkan Volcano Eruption Response Team), AVO staff also responded to eruptions on the Kamchatka Peninsula, details of which are summarized in Miller and Kurianov (1993). In 1993, AVO maintained seismic instrumentation networks on four volcanoes of the Cook Inlet region--Spurr, Redoubt, Iliamna, and Augustine--and two stations at Dutton Volcano near King Cove on the Alaska Peninsula. Other routine elements of AVO's volcano monitoring program in Alaska include periodic airborne measurement of volcanic SO2 and CO2 at Cook Inlet volcanoes (Doukas, 1995) and maintenance of a lightning detection system in Cook Inlet (Paskievitch and others, 1995).

The Geologic Story of Mount Rainier

USGS Publications Warehouse

Crandell, Dwight Raymond

1969-01-01

Ice-clad Mount Rainier, towering over the landscape of western Washington, ranks with Fuji-yama in Japan, Popocatepeti in Mexico, and Vesuvius in Italy among the great volcanoes of the world. At Mount Rainier, as at other inactive volcanoes, the ever-present possibility of renewed eruptions gives viewers a sense of anticipation, excitement, and apprehension not equaled by most other mountains. Even so, many of us cannot imagine the cataclysmic scale of the eruptions that were responsible for building the giant cone which now stands in silence. We accept the volcano as if it had always been there, and we appreciate only the beauty of its stark expanses of rock and ice, its flower-strewn alpine meadows, and its bordering evergreen forests.Mount Rainier owes its scenic beauty to many features. The broad cone spreads out on top of a major mountain range - the Cascades. The volcano rises about 7,000 feet above its 7,000-foot foundation, and stands in solitary splendor - the highest peak in the entire Cascade Range. Its rocky ice-mantled slopes above timberline contrast with the dense green forests and give Mount Rainier the appearance of an arctic island in a temperate sea, an island so large that you can see its full size and shape only from the air. The mountain is highly photogenic because of the contrasts it offers among bare rock, snowfields, blue sky, and the incomparable flower fields that color its lower slopes, shadows cast by the multitude of cliffs, ridges, canyons, and pinnacles change constantly from sunrise to sunset, endlessly varying the texture and mood of the mountain. The face of the mountain also varies from day to day as its broad snowfields melt during the summer. The melting of these frozen reservoirs makes Mount Rainier a natural resource in a practical as well as in an esthetic sense, for it ensures steady flows of water for hydroelectric power in the region, regardless of season.Seen from the Puget Sound country to the west, Mount Rainier has an unreal quality - its white summit, nearly 3 miles high, seems to float among the clouds. We share with the populace of the entire lowland a thrill as we watch skyward the evening's setting sun reddens the volcano's western snowfields. When you approach the mountain in its lovely setting, you may find something that appeals especially to you - the scenery, the wildlife, the glaciers, or the wildflowers. Or you may feel challenged to climb to the summit. Mount Rainier and its neighboring mountains have a special allure for a geologist because he visualizes the event - some ordinary, some truly spectacular - that made the present landscape. Such is the fascination of geology. A geologist becomes trained to see 'in his mind's eye' geologic events of thousands or even millions of years ago. And, most remarkable, he can 'see' these events by studying rocks in a cliff or roadcut, or perhaps by examining earthy material that looks like common soil beneath pastureland many miles away from the volcano.Our key to understanding the geology of Mount Rainier is that each geologic event can be reconstructed - or imagined - from the rocks formed at the time of the event. With this principle as our guide, we will review the geologic ancestry of this majestic volcano and learn what is behind its scenery.

"Mediterranean volcanoes vs. chain volcanoes in the Carpathians"

NASA Astrophysics Data System (ADS)

Chivarean, Radu

2017-04-01

Volcanoes have always represent an attractive subject for students. Europe has a small number of volcanoes and Romania has none active ones. The curricula is poor in the study of volcanoes. We want to make a parallel between the Mediterranean active volcanoes and the old extinct ones in the Oriental Carpathians. We made an comparison of the two regions in what concerns their genesis, space and time distribution, the specific relief and the impact in the landscape, consequences of their activities, etc… The most of the Mediterranean volcanoes are in Italy, in the peninsula in Napoli's area - Vezuviu, Campi Flegrei, Puzzoli, volcanic islands in Tirenian Sea - Ischia, Aeolian Islands, Sicily - Etna and Pantelleria Island. Santorini is located in Aegean Sea - Greece. Between Sicily and Tunisia there are 13 underwater volcanoes. The island called Vulcano, it has an active volcano, and it is the origin of the word. Every volcano in the world is named after this island, just north of Sicily. Vulcano is the southernmost of the 7 main Aeolian Islands, all volcanic in origin, which together form a small island arc. The cause of the volcanoes appears to be a combination of an old subduction event and tectonic fault lines. They can be considered as the origin of the science of volcanology. The volcanism of the Carpathian region is part of the extensive volcanic activity in the Mediterranean and surrounding regions. The Carpathian Neogene/Quaternary volcanic arc is naturally subdivided into six geographically distinct segments: Oas, Gutai, Tibles, Calimani, Gurghiu and Harghita. It is located roughly between the Carpathian thrust-and-fold arc to the east and the Transylvanian Basin to the west. It formed as a result of the convergence between two plate fragments, the Transylvanian micro-plate and the Eurasian plate. Volcanic edifices are typical medium-sized andesitic composite volcanoes, some of them attaining the caldera stage, complicated by submittal or peripheral domes or dome complexes. Dacitic volcanoes are smaller in size and consist of lava dome complexes, in places with associated pyroclastic cones and volcanic aprons. The volcanic history of Carpathian volcanic chain lasts since ca. 15 Ma, with the youngest occurring in the southern chain-terminus; the last eruption of Ciomadu volcano (Harghita) was ca. 10000 years ago. Using the knowledge acquired during the compulsory curriculum and complementary activities we we consider that the outdoor education is the best way to establish a relationship between the theory and the landscape reality in the field. As a follow up to our theoretical approach for the Earth's crust we organized two study trips in our region. During the first one the students could walk in a real crater, see scoria deposits and admire the basalt columns from Racos. In the second activity they could climb the Ciomadu volcano and go down to observe the crater lake St. Anna, the single volcanic lake in central Europe.

GlobVolcano: Earth Observation Services for Global Monitroing of Active Volcanoes

NASA Astrophysics Data System (ADS)

Borgstrom, S.; Bianchi, M.; Bronson, W.; Tampellini, M. L.; Ratti, R.; Seifert, F. M.; Komorowski, J. C.; Kaminski, E.; Peltier, A.; Van der Voet, P.

2010-03-01

The GlobVolcano project (2007-2010) is part of the Data User Element (DUE) programme of the European Space Agency (ESA).The objective of the project is to demonstrate EO-based (Earth Observation) services able to support the Volcano Observatories and other mandate users (Civil Protection, volcano scientific community) in their monitoring activities.The set of offered EO based information products is the following:- Deformation Mapping- Surface Thermal Anomalies- Volcanic Gas Emission- Volcanic Ash TrackingThe Deformation Mapping service is performed exploiting either PSInSARTM or Conventional DInSAR (EarthView® InSAR). The processing approach is selected according to the availability of SAR data and users' requests.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. Users are directly and actively involved in the validation of the Earth Observation products, by comparing them with ground data available at each site.In a first phase, the GlobVolcano Information System was designed, implemented and validated, involving a limited number of test areas and respective user organizations (Colima in Mexico, Merapi in Indonesia, Soufrière Hills in Montserrat Island, Piton de la Fournaise in La Reunion Island, Karthala in Comore Islands, Stromboli and Volcano in Italy). In particular Deformation Mapping results obtained for Piton de la Fournaise were compared with deformation rates measured by the volcano observatory using GPS stations and tiltmeters. IPGP (Institut de Physique du Globe de Paris) is responsible for the validation activities.The second phase of the project (currently on-going) concerns the service provision on pre-operational basis. Fifteen volcanic sites located in four continents are monitored and as many user organizations are involved and cooperating with the project team.In addition to the proprietary tools mentioned before, in phase two also the ROI_PAC software will be testsed for PALSAR processing on the Arenal volcano (Costa Rica).The GlobVolcano Information System includes two main elements:-The GlobVolcano Data Processing System, which consists of EO data processing subsystems located at each respective service centre.-The GlobVolcano Information Service, which is the provision infrastructure, including three elements: GlobV olcano Products Archives, GlobVolcano Metadata Catalogue, GlobVolcano User Interface (GVUI). The GlobVolcano Information System represents a significant step ahead towards the implementation of an operational, global observatory of volcanoes by a synergetic use of data from currently available Earth Observational satellites.

Initiative for the creation of an integrated infrastructure of European Volcano Observatories

NASA Astrophysics Data System (ADS)

Puglisi, G.; Bachelery, P.; Ferreira, T. J. L.; Vogfjörd, K. S.

2012-04-01

Active volcanic areas in Europe constitute a direct threat to millions of European citizens. The recent Eyjafjallajökull eruption also demonstrated that indirect effects of volcanic activity can present a threat to the economy and the lives of hundreds of million of people living in the whole continental area even in the case of activity of volcanoes with sporadic eruptions. Furthermore, due to the wide political distribution of the European territories, major activities of "European" volcanoes may have a worldwide impact (e.g. on the North Atlantic Ocean, West Indies included, and the Indian Ocean). Our ability to understand volcanic unrest and forecast eruptions depends on the capability of both the monitoring systems to effectively detect the signals generated by the magma rising and on the scientific knowledge necessary to unambiguously interpret these signals. Monitoring of volcanoes is the main focus of volcano observatories, which are Research Infrastructures in the ESFRI vision, because they represent the basic resource for researches in volcanology. In addition, their facilities are needed for the design, implementation and testing of new monitoring techniques. Volcano observatories produce a large amount of monitoring data and represent extraordinary and multidisciplinary laboratories for carrying out innovative joint research. The current distribution of volcano observatories in Europe and their technological state of the art is heterogeneous because of different types of volcanoes, different social requirements, operational structures and scientific background in the different volcanic areas, so that, in some active volcanic areas, observatories are lacking or poorly instrumented. Moreover, as the recent crisis of the ash in the skies over Europe confirms, the assessment of the volcanic hazard cannot be limited to the immediate areas surrounding active volcanoes. The whole European Community would therefore benefit from the creation of a network of volcano observatories, which would enable strengthening and sharing the technological and scientific level of current infrastructures. Such a network could help to achieve the minimum goal of deploying an observatory in each active volcanic area, and lay the foundation for an efficient and effective volcanic monitoring system at the European level.

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

USGS Publications Warehouse

Trusdell, Frank A.

2012-01-01

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

Seismic structures beneath Popocatepetl (Mexico) and Gorely (Kamchatka) volcanoes derived from passive tomography studies

NASA Astrophysics Data System (ADS)

Kuznetsov, Pavel; Koulakov, Ivan

2014-05-01

A number of active volcanoes are observed in different parts of the world, and they attract great interest of scientists. Comparing their characteristics helps in understanding the origin and mechanisms of their activity. One of the most effective methods for studying the deep structure beneath volcanoes is passive source seismic tomography. In this study we present results of tomographic inversions for two active volcanoes located in different parts of the world: Popocatepetl (Mexico) and Gorely (Kamchatka, Russia). In the past century both volcanoes were actively erupted that explains great interest to their detailed investigations. In both cases we made the full data analysis starting from picking the arrival times from local events. In the case of the Popocatepetl study, a temporary seismological network was deployed by GFZ for the period from December 1999 to July 2000. Note that during this period there were a very few events recorded inside the volcano. Most of recorded earthquakes occurred in surrounding areas and they probably have the tectonic nature. We performed a special analysis to ground the efficiency of using these data for studying seismic structure beneath the network installed on the volcano. The tomographic inversion was performed using the LOTOS code by Koulakov (2009). Beneath the Popocatepetl volcano we have found a zone of strong anti-correlation between P- and S-velocities that leaded to high values of Vp/Vs ratio. Similar features were found for some other volcanoes in previous studies. We interpret these anomalies as zones of high content of fluids and melts that are related to active magma sources. For the case of Gorely volcano we used the data of a temporary network just deployed in summer 2013 by our team from IPGG, Novosibirsk. Luckily, during the field works, the volcano started to manifest strong seismic activity. In this period, 100 - 200 volcanic events occurred daily. We collected the continuous seismic records from 20 stations for 5-7 days that gives us the possibility to locate several hundreds of events and to build a preliminary seismic model beneath the Gorely volcano. We found a zone of low S-velocity located beneath the SE flank of the volcano, just between the Gorely and Mutnovsky volcanoes. This may serve as an argument for feeding these volcanoes from a single source. Although Popocatepetl and Gorely volcanoes are considerably different in their size and eruption characteristics, we found some similar features in the seismic structures, such as anti-correlation of P- and S- anomalies and high Vp/Vs ratio patterns below summits. This provides common patterns that give us the keys for understanding the general mechanism of working the volcanic systems. This study was partly supported by the projects #7.3 of BES RAS, IP SB RAS #20 and IP SB-FEB RAS #42

Catalog of earthquake hypocenters at Alaskan volcanoes: January 1 through December 31, 2005

USGS Publications Warehouse

Dixon, James P.; Stihler, Scott D.; Power, John A.; Tytgat, Guy; Estes, Steve; McNutt, Stephen R.

2006-01-01

The Alaska Volcano Observatory (AVO), a cooperative program of the U.S. Geological Survey, the Geophysical Institute of the University of Alaska Fairbanks, and the Alaska Division of Geological and Geophysical Surveys, has maintained seismic monitoring networks at historically active volcanoes in Alaska since 1988 (Figure 1). The primary objectives of the seismic program are the real-time seismic monitoring of active, potentially hazardous, Alaskan volcanoes and the investigation of seismic processes associated with active volcanism. This catalog presents calculated earthquake hypocenters and seismic phase arrival data, and details changes in the seismic monitoring program for the period January 1 through December 31, 2005.The AVO seismograph network was used to monitor the seismic activity at thirty-two volcanoes within Alaska in 2005 (Figure 1). The network was augmented by two new subnetworks to monitor the Semisopochnoi Island volcanoes and Little Sitkin Volcano. Seismicity at these volcanoes was still being studied at the end of 2005 and has not yet been added to the list of permanently monitored volcanoes in the AVO weekly update. Following an extended period of monitoring to determine the background seismicity at the Mount Peulik, Ukinrek Maars, and Korovin Volcano, formal monitoring of these volcanoes began in 2005. AVO located 9,012 earthquakes in 2005.Monitoring highlights in 2005 include: (1) seismicity at Mount Spurr remaining above background, starting in February 2004, through the end of the year and into 2006; (2) an increase in seismicity at Augustine Volcano starting in May 2005, and continuing through the end of the year into 2006; (3) volcanic tremor and seismicity related to low-level strombolian activity at Mount Veniaminof in January to March and September; and (4) a seismic swarm at Tanaga Volcano in October and November.This catalog includes: (1) descriptions and locations of seismic instrumentation deployed in the field in 2005; (2) a description of earthquake detection, recording, analysis, and data archival systems; (3) a description of seismic velocity models used for earthquake locations; (4) a summary of earthquakes located in 2005; and (5) an accompanying UNIX tar-file with a summary of earthquake origin times, hypocenters, magnitudes, phase arrival times, and location quality statistics; daily station usage statistics; and all HYPOELLIPSE files used to determine the earthquake locations in 2005.

Strong S-wave attenuation and actively degassing magma beneath Taal volcano, Philippines, inferred from source location analysis using high-frequency seismic amplitudes

NASA Astrophysics Data System (ADS)

Kumagai, H.; Lacson, R. _Jr., Jr.; Maeda, Y.; Figueroa, M. S., II; Yamashina, T.

2014-12-01

Taal volcano, Philippines, is one of the world's most dangerous volcanoes given its history of explosive eruptions and its close proximity to populated areas. A key feature of these eruptions is that the eruption vents were not limited to Main Crater but occurred on the flanks of Volcano Island. This complex eruption history and the fact that thousands of people inhabit the island, which has been declared a permanent danger zone, together imply an enormous potential for disasters. The Philippine Institute of Volcanology and Seismology (PHIVOLCS) constantly monitors Taal, and international collaborations have conducted seismic, geodetic, electromagnetic, and geochemical studies to investigate the volcano's magma system. Realtime broadband seismic, GPS, and magnetic networks were deployed in 2010 to improve monitoring capabilities and to better understand the volcano. The seismic network has recorded volcano-tectonic (VT) events beneath Volcano Island. We located these VT events based on high-frequency seismic amplitudes, and found that some events showed considerable discrepancies between the amplitude source locations and hypocenters determined by using onset arrival times. Our analysis of the source location discrepancies points to the existence of a region of strong S-wave attenuation near the ground surface beneath the east flank of Volcano Island. This region is beneath the active fumarolic area and above sources of pressure contributing inflation and deflation, and it coincides with a region of high electrical conductivity. The high-attenuation region matches that inferred from an active-seismic survey conducted at Taal in 1993. Our results, synthesized with previous results, suggest that this region represents actively degassing magma near the surface, and imply a high risk of future eruptions on the east flank of Volcano Island.

Floristic similarity, diversity and endemism as indicators of refugia characteristics and needs in the West

USGS Publications Warehouse

Malanson, George P.; Zimmerman, Dale L.; Fagre, Daniel B.

2015-01-01

The floras of mountain ranges, and their similarity, beta diversity and endemism, are indicative of processes of community assembly; they are also the initial conditions for coming disassembly and reassembly in response to climate change. As such, these characteristics can inform thinking on refugia. The published floras or approximations for 42 mountain ranges in the three major mountain systems (Sierra-Cascades, Rocky Mountains and Great Basin ranges) across the western USA and southwestern Canada were analysed. The similarity is higher among the ranges of the Rockies while equally low among the ranges of the Sierra-Cascades and Great Basin. Mantel correlations of similarity with geographic distance are also higher for the Rocky Mountains. Endemism is relatively high, but is highest in the Sierra-Cascades (due to the Sierra Nevada as the single largest range) and lowest in the Great Basin, where assemblages are allochthonous. These differences indicate that the geologic substrates of the Cascade volcanoes, which are much younger than any others, play a role in addition to geographic isolation in community assembly. The pattern of similarity and endemism indicates that the ranges of the Cascades will not function well as stepping stones and the endemic species that they harbor may need more protection than those of the Rocky Mountains. The geometry of the ranges is complemented by geology in setting the stage for similarity and the potential for refugia across the West. Understanding the geographic template as initial conditions for the future can guide the forecast of refugia and related monitoring or protection efforts.

The Evolution of Galápagos Volcanoes: An Alternative Perspective

NASA Astrophysics Data System (ADS)

Harpp, Karen S.; Geist, Dennis J.

2018-05-01

The older eastern Galápagos are different in almost every way from the historically active western Galápagos volcanoes. The western Galápagos volcanoes have steep upper slopes and are topped by large calderas, whereas none of the older islands has a caldera, an observation that is supported by recent gravity measurements. Moreover, the eastern islands tend to have been constructed by linear fissure systems and many are cut by faults. Most of the western volcanoes erupt evolved basalts with an exceedingly small range of Mg#, Lan/Smn, and Smn/Ybn. This is attributed to homogenization in a crustal-scale magmatic mush column, which is maintained in a thermochemical steady state, owing to high magma supply directly over the Galápagos mantle plume. The exceptions are volcanoes at the leading edge of the hotspot, which have yet to develop mush columns, and volcanoes that are waning in activity, because they are being carried away from the plume. In contrast, the eastern volcanoes erupt relatively primitive magmas, with a large range in Mg#, Lan/Smn, and Smn/Ybn. This is attributed to isolated, ephemeral magmatic plumbing systems supplied by smaller magmatic fluxes throughout their histories. Consequently, each batch of magma follows an independent course of evolution, owing to the low volume of hypersolidus material beneath these volcanoes. The magmatic flux to Galápagos volcanoes negatively correlates with the distance to the Galápagos Spreading Center (GSC). When the ridge was close to the plume, most of the plume-derived magma was directed to the ridge. Currently, the active volcanoes are much farther from the GSC, thus most of the plume-derived magma erupts on the Nazca Plate and can be focused beneath the large young shields. We define an intermediate sub-province comprising Rabida, Santiago and Pinzon volcanoes, which were most active about 1 Ma. They have all erupted dacites, rhyolites, and trachytes, similar to the dying stage of the western volcanoes, indicating that there was a relatively large volume of mush beneath them. Morphologically, however, they are more like the eastern volcanoes, and have erupted lavas with a large range in composition.

Catalogue of satellite photography of the active volcanoes of the world

NASA Technical Reports Server (NTRS)

Heiken, G.

1976-01-01

A catalogue is presented of active volcanoes as viewed from Earth-orbiting satellites. The listing was prepared of photographs, which have been screened for quality, selected from the earth resources technology satellite (ERTS) and Skylab, Apollo and Gemini spacecraft. There is photography of nearly every active volcano in the world; the photographs are particularly useful for regional studies of volcanic fields.

Volcanoes.

ERIC Educational Resources Information Center

Tilling, Robert I.

One of a series of general interest publications on science topics, this booklet provides a non-technical introduction to the subject of volcanoes. Separate sections examine the nature and workings of volcanoes, types of volcanoes, volcanic geological structures such as plugs and maars, types of eruptions, volcanic-related activity such as geysers…

Is the seismicity swarm at long-dormant Jailolo volcano (Indonesia) a signature of a magmatic unrest?

NASA Astrophysics Data System (ADS)

Passarelli, Luigi; Cesca, Simone; Heryandoko, Nova; Lopez Comino, Jose Angel; Strollo, Angelo; Rivalta, Eleonora; Rohadi, Supryianto; Dahm, Torsten; Milkereit, Claus

2017-04-01

Magmatic unrest is challenging to detect when monitoring is sparse and there is little knowledge about the volcano. This is especially true for long-dormant volcanoes. Geophysical observables like seismicity, deformation, temperature and gas emission are reliable indicators of ongoing volcanic unrest caused by magma movements. Jailolo volcano is a Holocene volcano belonging to the Halmahera volcanic arc in the Northern Moluccas Islands, Indonesia. Global databases of volcanic eruptions have no records of its eruptive activity and no geological investigation has been carried out to better assess the past eruptive activity at Jailolo. It probably sits on the northern rim of an older caldera which now forms the Jailolo bay. Hydrothermal activity is intense with several hot-springs and steaming ground spots around the Jailolo volcano. In November 2015 an energetic seismic swarm started and lasted until late February 2016 with four earthquakes with M>5 recorded by global seismic networks. At the time of the swarm no close geophysical monitoring network was available around Jailolo volcano except for a broadband station at 30km distant. We installed last summer a local dense multi-parametric monitoring network with 36 seismic stations, 6 GPS and 2 gas monitoring stations around Jailolo volcano. We revised the focal mechanisms of the larger events and used single station location methods in order to exploit the little information available at the time of the swarm activity. We also combined the old sparse data with our local dense network. Migration of hypocenters and inversion of the local stress field derived by focal mechanisms analysis indicate that the Nov-Feb seismicity swarm may be related to a magmatic intrusion at shallow depth. Data from our dense network confirms ongoing micro-seismic activity underneath Jailolo volcano but there are no indications of new magma intrusion. Our findings indicate that magmatic unrest occurred at Jailolo volcano and call for a revision of the volcanic hazard.

A comprehensive Probabilistic Tsunami Hazard Assessment for the city of Naples (Italy)

NASA Astrophysics Data System (ADS)

Anita, G.; Tonini, R.; Selva, J.; Sandri, L.; Pierdominici, S.; Faenza, L.; Zaccarelli, L.

2012-12-01

A comprehensive Probabilistic Tsunami Hazard Assessment (PTHA) should consider different tsunamigenic sources (seismic events, slide failures, volcanic eruptions) to calculate the hazard on given target sites. This implies a multi-disciplinary analysis of all natural tsunamigenic sources, in a multi-hazard/risk framework, which considers also the effects of interaction/cascade events. Our approach shows the ongoing effort to analyze the comprehensive PTHA for the city of Naples (Italy) including all types of sources located in the Tyrrhenian Sea, as developed within the Italian project ByMuR (Bayesian Multi-Risk Assessment). The project combines a multi-hazard/risk approach to treat the interactions among different hazards, and a Bayesian approach to handle the uncertainties. The natural potential tsunamigenic sources analyzed are: 1) submarine seismic sources located on active faults in the Tyrrhenian Sea and close to the Southern Italian shore line (also we consider the effects of the inshore seismic sources and the associated active faults which we provide their rapture properties), 2) mass failures and collapses around the target area (spatially identified on the basis of their propensity to failure), and 3) volcanic sources mainly identified by pyroclastic flows and collapses from the volcanoes in the Neapolitan area (Vesuvius, Campi Flegrei and Ischia). All these natural sources are here preliminary analyzed and combined, in order to provide a complete picture of a PTHA for the city of Naples. In addition, the treatment of interaction/cascade effects is formally discussed in the case of significant temporary variations in the short-term PTHA due to an earthquake.

Living with a volcano in your backyard: an educator's guide with emphasis on Mount Rainier

USGS Publications Warehouse

Driedger, Carolyn L.; Doherty, Anne; Dixon, Cheryl; Faust, Lisa M.

2005-01-01

The National Park Service and the U.S. Geological Survey’s Volcano Hazards Program (USGS-VHP) support development and publication of this educator’s guide as part of their mission to educate the public about volcanoes. The USGS-VHP studies the dynamics of volcanoes, investigates eruption histories, develops hazard assessments, monitors volcano-related activity, and collaborates with local officials to lower the risk of disruption when volcanoes become restless.

Volcanic hazards and remote sensing in Pacific Latin America

NASA Astrophysics Data System (ADS)

Lyons, John; Rose, Bill; Escobar, Rüdiger

2011-06-01

PASI Workshop on Open Vent Volcanoes; San José, Costa Rica, 10-24 January 2011 ; Open-vent volcanoes are a class of volcano that contain a relatively open path from the subsurface to the atmosphere without a major vent obstruction. Their persistent, low-level activity, which poses little danger to communities, may be punctuated by violent activity without warning. These complex systems challenge and provide opportunity for observatories and national and international investigators. Long-lived eruptions are also laboratories for students and scientists and a locus for developing collaborations and field testing new instrumentation and methods. Pacific Latin America hosts a high density of active volcanoes, and many are under-monitored and under-researched despite the efforts of local volcano observatories and their accessibility to U.S. and European scientists.

Earth Observations taken by the Expedition 16 Crew

NASA Image and Video Library

2007-11-17

ISS016-E-010894 (17 Nov. 2007) --- Cosiguina Volcano, Nicaragua is featured in this image photographed by an Expedition 16 crewmember on the International Space Station. Three Central American countries (El Salvador, Honduras, and Nicaragua) include coastline along the Gulf of Fonseca that opens into the Pacific Ocean. The southern boundary of the Gulf is a peninsula formed by the Cosiguina volcano illustrated in this view. Cosiguina is a stratovolcano, typically tall cone-shaped structures formed by alternating layers of solidified lava and volcanic rocks (ash, pyroclastic flows, breccias) produced by explosive eruptions. The summit crater is filled with a lake (Laguna Cosiguina). The volcano last erupted in 1859, but its most famous activity occurred in 1835 when it produced the largest historical eruption in Nicaragua. Ash from the 1835 eruption has been found in Mexico, Costa Rica, and Jamaica. The volcano has been quiet since 1859, only an instant in terms of geological time. An earthquake swarm was measured near Cosiguina in 2002, indicating that tectonic forces are still active in the region although the volcano is somewhat isolated from the line of more recently active Central American volcanoes to the northwest and southeast. Intermittently observed gas bubbles in Laguna Cosiguina, and a hot spring along the eastern flank of the volcano are the only indicators of hydrothermal activity at the volcano. The fairly uniform vegetation cover (green) on the volcano's sides also attest to a general lack of gas emissions or "hot spots" on the 872 meter high cone, according to NASA scientists who study the photos downlinked from the orbital outpost.

Volcanic hazards at Mount Rainier, Washington

USGS Publications Warehouse

Crandell, Dwight Raymond; Mullineaux, Donal Ray

1967-01-01

Mount Rainier is a large stratovolcano of andesitic rock in the Cascade Range of western Washington. Although the volcano as it now stands was almost completely formed before the last major glaciation, geologic formations record a variety of events that have occurred at the volcano in postglacial time. Repetition of some of these events today without warning would result in property damage and loss of life on a catastrophic scale. It is appropriate, therefore, to examine the extent, frequency, and apparent origin of these phenomena and to attempt to predict the effects on man of similar events in the future. The present report was prompted by a contrast that we noted during a study of surficial geologic deposits in Mount Rainier National Park, between the present tranquil landscape adjacent to the volcano and the violent events that shaped parts of that same landscape in the recent past. Natural catastrophes that have geologic causes - such as eruptions, landslides, earthquakes, and floods - all too often are disastrous primarily because man has not understood and made allowance for the geologic environment he occupies. Assessment of the potential hazards of a volcanic environment is especially difficult, for prediction of the time and kind of volcanic activity is still an imperfect art, even at active volcanoes whose behavior has been closely observed for many years. Qualified predictions, however, can be used to plan ways in which hazards to life and property can be minimized. The prediction of eruptions is handicapped because volcanism results from conditions far beneath the surface of the earth, where the causative factors cannot be seen and, for the most part, cannot be measured. Consequently, long-range predictions at Mount Rainier can be based only on the past behavior of the volcano, as revealed by study of the deposits that resulted from previous eruptions. Predictions of this sort, of course, cannot be specific as to time and locale of future events, and clearly are valid only if the past behavior is, as we believe, a reliable guide. The purpose of this report is to infer the events recorded by certain postglacial deposits at Mount Rainier and to suggest what bearing similar events in the future might have on land use within and near the park. In addition, table 2 (page 22) gives possible warning signs of an impending eruption. We want to increase man's understanding of a possibly hazardous geologic environment around Mount Rainier volcano, yet we do not wish to imply for certain that the hazards described are either immediate or inevitable. However, we do believe that hazards exist, that some caution is warranted, and that some major hazards can be avoided by judicious planning. Most of the events with which we are concerned are sporadic phenomena that have resulted directly or indirectly from volcanic eruptions. Although no eruptions (other than steam emission) of the volcano in historic time are unequivocally known (Hopson and others, 1962), pyroclastic (air-laid) deposits of pumice and rock debris attest to repeated, widely spaced eruptions during the 10,000 years or so of postglacial time. In addition, the constituents of some debris flows indicate an origin during eruptions of molten rock; other debris flows, because of their large size and constituents, are believed to have been caused by steam explosions. Some debris flows, however, are not related to volcanism at all.

Costa Rica's Chain of laterally collapsed volcanoes.

NASA Astrophysics Data System (ADS)

Duarte, E.; Fernandez, E.

2007-05-01

From the NW extreme to the SW end of Costa Rica's volcanic backbone, a number of laterally collapsed volcanoes can be observed. Due to several factors, attention has been given to active volcanoes disregarding the importance of collapsed features in terms of assessing volcanic hazards for future generations around inhabited volcanoes. In several cases the typical horseshoe shape amphitheater-like depression can be easily observed. In other cases due to erosion, vegetation, topography, seismic activity or drastic weather such characteristics are not easily recognized. In the order mentioned above appear: Orosi-Cacao, Miravalles, Platanar, Congo, Von Frantzius, Cacho Negro and Turrialba volcanoes. Due to limited studies on these structures it is unknown if sector collapse occurred in one or several phases. Furthermore, in the few studied cases no evidence has been found to relate collapses to actual eruptive episodes. Detailed studies on the deposits and materials composing dome-like shapes will shed light on unsolved questions about petrological and chemical composition. Volume, form and distance traveled by deposits are part of the questions surrounding most of these collapsed volcanoes. Although most of these mentioned structures are extinct, at least Irazú volcano (active volcano) has faced partial lateral collapses recently. It did presented strombolian activity in the early 60s. Collapse scars show on the NW flank show important mass removal in historic and prehistoric times. Moreover, in 1994 a minor hydrothermal explosion provoked the weakening of a deeply altered wall that holds a crater lake (150m diameter, 2.6x106 ). A poster will depict images of the collapsed volcanoes named above with mayor descriptive characteristics. It will also focus on the importance of deeper studies to assess the collapse potential of Irazú volcano with related consequences. Finally, this initiative will invite researchers interested in such topic to join future studies in these Costarrican volcanoes.

HCMM: Soil moisture in relation to geologic structure and lithology, northern California

NASA Technical Reports Server (NTRS)

Rich, E. I. (Principal Investigator)

1980-01-01

The author has identified the following significant results. Detailed examination of Nite-IR images of intermontane basins in arid and/or semiarid areas of California discloses a ring or halo of relatively lighter greytone around the edges of each basin. Intermontane basins in the Northern Coast Range, however, do not show this thermal haloing. The topographic elevation of the haloes in arid basins shows seasonal variation, but it is present on nearly all images. A similar halo encircles many of the volcanoes on the Modoc Plateau and Southern Cascade Range. Although the halo around the arid intermontane basins can possibly be explained in relation to the location of alluvial fans (and perhaps water content of the rocks), a similar explanation cannot be made for the haloes around volcanoes or for the lack of haloes around basins in the Coast Range. Atmospheric thermal layering may be an alternative explanation; however, this explanation is also riddled with inconsistencies.

Spreading and collapse of big basaltic volcanoes

NASA Astrophysics Data System (ADS)

Puglisi, Giuseppe; Bonforte, Alessandro; Guglielmino, Francesco; Peltier, Aline; Poland, Michael

2016-04-01

Among the different types of volcanoes, basaltic ones usually form the most voluminous edifices. Because volcanoes are growing on a pre-existing landscape, the geologic and structural framework of the basement (and earlier volcanic landforms) influences the stress regime, seismicity, and volcanic activity. Conversely, the masses of these volcanoes introduce a morphological anomaly that affects neighboring areas. Growth of a volcano disturbs the tectonic framework of the region, clamps and unclamps existing faults (some of which may be reactivated by the new stress field), and deforms the substratum. A volcano's weight on its basement can trigger edifice spreading and collapse that can affect populated areas even at significant distance. Volcano instability can also be driven by slow tectonic deformation and magmatic intrusion. The manifestations of instability span a range of temporal and spatial scales, ranging from slow creep on individual faults to large earthquakes affecting a broad area. In the frame of MED-SVU project, our work aims to investigate the relation between basement setting and volcanic activity and stability at three Supersite volcanoes: Etna (Sicily, Italy), Kilauea (Island of Hawaii, USA) and Piton de la Fournaise (La Reunion Island, France). These volcanoes host frequent eruptive activity (effusive and explosive) and share common features indicating lateral spreading and collapse, yet they are characterized by different morphologies, dimensions, and tectonic frameworks. For instance, the basaltic ocean island volcanoes of Kilauea and Piton de la Fournaise are near the active ends of long hotspot chains while Mt. Etna has developed at junction along a convergent margin between the African and Eurasian plates and a passive margin separating the oceanic Ionian crust from the African continental crust. Magma supply and plate velocity also differ in the three settings, as to the sizes of the edifices and the extents of their rift zones. These Supersite volcanoes, due to their similarities and differences, coupled with their long-time and high-level monitoring networks, represent the best natural laboratories for investigating the manifestations and mechanisms of spreading and collapse, the feedback process between spreading and eruptive activity (especially along rift zones), and the role of the regional geodynamics.

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

USGS Publications Warehouse

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.

2007 Volcanic activity in Alaska, Kamchatka, and the Kurile Islands: Summary of events and response of the Alaska Volcano Observatory

USGS Publications Warehouse

McGimsey, Robert G.; Neal, Christina A.; Dixon, James P.; Malik, Nataliya; Chibisova, Marina

2011-01-01

The Alaska Volcano Observatory (AVO) responded to eruptions, possible eruptions, and volcanic unrest at or near nine separate volcanic centers in Alaska during 2007. The year was highlighted by the eruption of Pavlof, one of Alaska's most frequently active volcanoes. Glaciated Fourpeaked Mountain, a volcano thought to have been inactive in the Holocene, produced a phreatic eruption in the autumn of 2006 and continued to emit copious amounts of steam and volcanic gas into 2007. Redoubt Volcano showed the first signs of the unrest that would unfold in 2008-09. AVO staff also participated in hazard communication and monitoring of multiple eruptions at seven volcanoes in Russia as part of its collaborative role in the Kamchatka and Sakhalin Volcanic Eruption Response Teams.

Ground survey of active Central American volcanoes in November - December 1973

NASA Technical Reports Server (NTRS)

Stoiber, R. E. (Principal Investigator); Rose, W. I., Jr.

1974-01-01

The author has identified the following significant results. Thermal anomalies at two volcanoes, Santiaguito and Izalco, have grown in size in the past six months, based on repeated ground survey. Thermal anomalies at Pacaya volcano have became less intense in the same period. Large (500 m diameter) thermal anomalies exist at 3 volcanoes presently, and smaller scale anomalies are found at nine other volcanoes.

A new method for monitoring global volcanic activity. [Alaska, Hawaii, Washington, California, Iceland, Guatemala, El Salvador, and Nicaragua

NASA Technical Reports Server (NTRS)

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

1974-01-01

The ERTS Data Collection System makes it feasible for the first time to monitor the level of activity at widely separated volcanoes and to relay these data rapidly to one central office for analysis. While prediction of specific eruptions is still an evasive goal, early warning of a reawakening of quiescent volcanoes is now a distinct possibility. A prototypical global volcano surveillance system was established under the ERTS program. Instruments were installed in cooperation with local scientists on 15 volcanoes in Alaska, Hawaii, Washington, California, Iceland, Guatemala, El Salvador and Nicaragua. The sensors include 19 seismic event counters that count four different sizes of earthquakes and six biaxial borehole tiltmeters that measure ground tilt with a resolution of 1 microradian. Only seismic and tilt data are collected because these have been shown in the past to indicate most reliably the level of volcano activity at many different volcanoes. Furthermore, these parameters can be measured relatively easily with new instrumentation.

The First Historical Eruption of Kambalny Volcano in 2017 .

NASA Astrophysics Data System (ADS)

Gordeev, E.

2017-12-01

The first historical eruption at Kambalny volcano began about 21:20 UTC on March 24, 2017 with powerful ash emissions up to 6 km above sea level from the pre-summit crater. According to tephrochronological data, it is assumed that the strong eruptions of the volcano occurred 200 (?) and 600 years ago. KVERT (Kamchatka Volcanic Eruption Response Team) of the Institute of Volcanology and Seismology FEB RAS has been monitoring Kambalny volcano since 2002. KVERT worked closely with AMC Elizovo and Tokyo VAAC during the eruption at Kambalny volcano in 2017. The maximum intensity of ash emissions occurred on 25-26 March: a continuous plume laden with ash particles spread over several thousand kilometers, changing the direction of propagation from the volcano from the south-west to the south and south-east. On 27-29 March, the ash plume extended to the west, on 30 March - to the southeast of the volcano. On March 31 and April 01, the volcano was relatively quiet. The resumption of the volcano activity after two days of rest was expressed in powerful ash emissions up to 7 km above sea level. Gas-steam plumes containing some amount of ash were noted on 02-05 April, and powerful ash emissions up to 7 km above sea level occurred on 09 April. The explosive activity at the volcano ended on 11 April. The area of ash deposits was about 1500 km2, the total area covered by ash falls, for example, on 25 March, was about 650 thousand km2. To monitor and study the Kambalny volcano eruption we mainly used satellite images of medium resolution available in the information system "Monitoring volcanic activity in Kamchatka and Kurile Islands" (VolSatView). This work was supported by the Russian Science Foundation, project No. 16-17-00042.

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

NASA Astrophysics Data System (ADS)

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.

Volcano hazards at Newberry Volcano, Oregon

USGS Publications Warehouse

Sherrod, David R.; Mastin, Larry G.; Scott, William E.; Schilling, Steven P.

1997-01-01

Newberry volcano is a broad shield volcano located in central Oregon. It has been built by thousands of eruptions, beginning about 600,000 years ago. At least 25 vents on the flanks and summit have been active during several eruptive episodes of the past 10,000 years. The most recent eruption 1,300 years ago produced the Big Obsidian Flow. Thus, the volcano's long history and recent activity indicate that Newberry will erupt in the future. The most-visited part of the volcano is Newberry Crater, a volcanic depression or caldera at the summit of the volcano. Seven campgrounds, two resorts, six summer homes, and two major lakes (East and Paulina Lakes) are nestled in the caldera. The caldera has been the focus of Newberry's volcanic activity for at least the past 10,000 years. Other eruptions during this time have occurred along a rift zone on the volcano's northwest flank and, to a lesser extent, the south flank. Many striking volcanic features lie in Newberry National Volcanic Monument, which is managed by the U.S. Forest Service. The monument includes the caldera and extends along the northwest rift zone to the Deschutes River. About 30 percent of the area within the monument is covered by volcanic products erupted during the past 10,000 years from Newberry volcano. Newberry volcano is presently quiet. Local earthquake activity (seismicity) has been trifling throughout historic time. Subterranean heat is still present, as indicated by hot springs in the caldera and high temperatures encountered during exploratory drilling for geothermal energy. This report describes the kinds of hazardous geologic events that might occur in the future at Newberry volcano. A hazard-zonation map is included to show the areas that will most likely be affected by renewed eruptions. In terms of our own lifetimes, volcanic events at Newberry are not of day-to-day concern because they occur so infrequently; however, the consequences of some types of eruptions can be severe. When Newberry volcano becomes restless, be it tomorrow or many years from now, the eruptive scenarios described herein can inform planners, emergency response personnel, and citizens about the kinds and sizes of events to expect.

The Colima Volcano WebGIS: system acquisition, application and database development in an open-source environment

NASA Astrophysics Data System (ADS)

Manea, M.; Norini, G.; Capra, L.; Manea, V. C.

2009-04-01

The Colima Volcano is currently the most active Mexican volcano. After the 1913 plinian activity the volcano presented several eruptive phases that lasted few years, but since 1991 its activity became more persistent with vulcanian eruptions, lava and dome extrusions. During the last 15 years the volcano suffered several eruptive episodes as in 1991, 1994, 1998-1999, 2001-2003, 2004 and 2005 with the emplacement of pyroclastic flows. During rain seasons lahars are frequent affecting several infrastructures such as bridges and electric towers. Researchers from different institutions (Mexico, USA, Germany, Italy, and Spain) are currently working on several aspects of the volcano, from remote sensing, field data of old and recent deposits, structural framework, monitoring (rain, seismicity, deformation and visual observations) and laboratory experiments (analogue models and numerical simulations). Each investigation is focused to explain a single process, but it is fundamental to visualize the global status of the volcano in order to understand its behavior and to mitigate future hazards. The Colima Volcano WebGIS represents an initiative aimed to collect and store on a systematic basis all the data obtained so far for the volcano and to continuously update the database with new information. The Colima Volcano WebGIS is hosted on the Computational Geodynamics Laboratory web server and it is based entirely on Open Source software. The web pages, written in php/html will extract information from a mysql relational database, which will host the information needed for the MapBender application. There will be two types of intended users: 1) researchers working on the Colima Volcano, interested in this project and collaborating in common projects will be provided with open access to the database and will be able to introduce their own data, results, interpretation or recommendations; 2) general users, interested in accessing information on Colima Volcano will be provided with restricted access and will be able to visualize maps, images, diagrams, and current activity. The website can be visited at: http://www.geociencias.unam.mx/colima

2005 Volcanic Activity in Alaska, Kamchatka, and the Kurile Islands: Summary of Events and Response of the Alaska Volcano Observatory

USGS Publications Warehouse

McGimsey, R.G.; Neal, C.A.; Dixon, J.P.; Ushakov, Sergey

2008-01-01

The Alaska Volcano Observatory (AVO) responded to eruptive activity or suspected volcanic activity at or near 16 volcanoes in Alaska during 2005, including the high profile precursory activity associated with the 2005?06 eruption of Augustine Volcano. AVO continues to participate in distributing information about eruptive activity on the Kamchatka Peninsula, Russia, and in the Kurile Islands of the Russian Far East, in conjunction with the Kamchatkan Volcanic Eruption Response Team (KVERT) and the Sakhalin Volcanic Eruption Response Team (SVERT), respectively. In 2005, AVO helped broadcast alerts about activity at 8 Russian volcanoes. The most serious hazard posed from volcanic eruptions in Alaska, Kamchatka, or the Kurile Islands is the placement of ash into the atmosphere at altitudes traversed by jet aircraft along the North Pacific and Russian Trans East air routes. AVO, KVERT, and SVERT work collaboratively with the National Weather Service, Federal Aviation Administration, and the Volcanic Ash Advisory Centers to provide timely warnings of volcanic eruptions and the production and movement of ash clouds.

Volcanic hotspots of the central and southern Andes as seen from space by ASTER and MODVOLC between the years 2000-2011

NASA Astrophysics Data System (ADS)

Jay, J.; Pritchard, M. E.; Mares, P. J.; Mnich, M. E.; Welch, M. D.; Melkonian, A. K.; Aguilera, F.; Naranjo, J.; Sunagua, M.; Clavero, J. E.

2011-12-01

We examine 153 volcanoes and geothermal areas in the central, southern, and austral Andes for temperature anomalies between 2000-2011 from two different spacebourne sensors: 1) those automatically detected by the MODVOLC algorithm (Wright et al., 2004) from MODIS and 2) manually identified hotspots in nighttime images from ASTER. Based on previous work, we expected to find 8 thermal anomalies (volcanoes: Ubinas, Villarrica, Copahue, Láscar, Llaima, Chaitén, Puyehue-Cordón Caulle, Chiliques). We document 31 volcanic areas with pixel integrated temperatures of 4 to more than 100 K above background in at least two images, and another 29 areas that have questionable hotspots with either smaller anomalies or a hotspot in only one image. Most of the thermal anomalies are related to known activity (lava and pyroclastic flows, growing lava domes, fumaroles, and lakes) while others are of unknown origin or reflect activity at volcanoes that were not thought to be active. A handful of volcanoes exhibit temporal variations in the magnitude and location of their temperature anomaly that can be related to both documented and undocumented pulses of activity. Our survey reveals that low amplitude volcanic hotspots detectable from space are more common than expected (based on lower resolution data) and that these features could be more widely used to monitor changes in the activity of remote volcanoes. We find that the shape, size, magnitude, and location on the volcano of the thermal anomaly vary significantly from volcano to volcano, and these variations should be considered when developing algorithms for hotspot identification and detection. We compare our thermal results to satellite InSAR measurements of volcanic deformation and find that there is no simple relationship between deformation and thermal anomalies - while 31 volcanoes have continuous hotspots, at least 17 volcanoes in the same area have exhibited deformation, and these lists do not completely overlap. In order to investigate the relationship between seismic and thermal volcanic activity, we examine seismic data for 5 of the volcanoes (Uturuncu, Olca-Paruma, Ollague, Irruputuncu, and Sol de Mañana) as well as seismological reports from the Chilean geological survey SERNAGEOMIN for 11 additional volcanoes. Although there were 7 earthquakes with Mw > 7 in our study area from 2000-2010, there is essentially no evidence from ASTER or MODVOLC that the thermal anomalies were affected by seismic shaking.

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

NASA Astrophysics Data System (ADS)

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.

An active seismic experiment at Tenerife Island (Canary Island, Spain): Imaging an active volcano edifice

NASA Astrophysics Data System (ADS)

Garcia-Yeguas, A.; Ibañez, J. M.; Rietbrock, A.; Tom-Teidevs, G.

2008-12-01

An active seismic experiment to study the internal structure of Teide Volcano was carried out on Tenerife, a volcanic island in Spain's Canary Islands. The main objective of the TOM-TEIDEVS experiment is to obtain a 3-dimensional structural image of Teide Volcano using seismic tomography and seismic reflection/refraction imaging techniques. At present, knowledge of the deeper structure of Teide and Tenerife is very limited, with proposed structural models mainly based on sparse geophysical and geological data. This multinational experiment which involves institutes from Spain, Italy, the United Kingdom, Ireland, and Mexico will generate a unique high resolution structural image of the active volcano edifice and will further our understanding of volcanic processes.

Gravitational sliding of the Mt. Etna massif along a sloping basement

NASA Astrophysics Data System (ADS)

Murray, John B.; van Wyk de Vries, Benjamin; Pitty, Andy; Sargent, Phil; Wooller, Luke

2018-04-01

Geological field evidence and laboratory modelling indicate that volcanoes constructed on slopes slide downhill. If this happens on an active volcano, then the movement will distort deformation data and thus potentially compromise interpretation. Our recent GPS measurements demonstrate that the entire edifice of Mt. Etna is sliding to the ESE, the overall direction of slope of its complex, rough sedimentary basement. We report methods of discriminating the sliding vector from other deformation processes and of measuring its velocity, which averaged 14 mm year-1 during four intervals between 2001 and 2012. Though sliding of one sector of a volcano due to flank instability is widespread and well-known, this is the first time basement sliding of an entire active volcano has been directly observed. This is important because the geological record shows that such sliding volcanoes are prone to devastating sector collapse on the downslope side, and whole volcano migration should be taken into account when assessing future collapse hazard. It is also important in eruption forecasting, as the sliding vector needs to be allowed for when interpreting deformation events that take place above the sliding basement within the superstructure of the active volcano, as might occur with dyke intrusion or inflation/deflation episodes.

Earth's Volcanoes and their Eruptions; the 3rd edition of the Smithsonian Institution's Volcanoes of the World

NASA Astrophysics Data System (ADS)

Siebert, L.; Simkin, T.; Kimberly, P.

2010-12-01

The 3rd edition of the Smithsonian Institution’s Volcanoes of the World incorporates data on the world’s volcanoes and their eruptions compiled since 1968 by the Institution’s Global Volcanism Program (GVP). Published this Fall jointly by the Smithsonian and the University of California Press, it supplements data from the 1994 2nd edition and includes new data on the number of people living in proximity to volcanoes, the dominant rock lithologies at each volcano, Holocene caldera-forming eruptions, and preliminary lists of Pleistocene volcanoes and large-volume Pleistocene eruptions. The 3rd edition contains data on nearly 1550 volcanoes of known or possible Holocene age, including chronologies, characteristics, and magnitudes for >10,400 Holocene eruptions. The standard 20 eruptive characteristics of the IAVCEI volcano catalog series have been modified to include dated vertical edifice collapse events due to magma chamber evacuation following large-volume explosive eruptions or mafic lava effusion, and lateral sector collapse. Data from previous editions of Volcanoes of the World are also supplemented by listings of up to the 5 most dominant lithologies at each volcano, along with data on population living within 5, 10, 30, and 100 km radii of each volcano or volcanic field. Population data indicate that the most populated regions also contain the most frequently active volcanoes. Eruption data document lava and tephra volumes and Volcanic Explosivity Index (VEI) assignments for >7800 eruptions. Interpretation of VRF data has led to documentation of global eruption rates and the power law relationship between magnitude and frequency of volcanic eruptions. Data with volcanic hazards implications include those on fatalities and evacuations and the rate at which eruptions reach their climax. In recognition of the hazards implications of potential resumption of activity at pre-Holocene volcanoes, the 3rd edition includes very preliminary lists of Pleistocene volcanoes and large-volume Pleistocene eruptions, the latter in collaboration with the VOGRIPA project of Steve Sparks and colleagues. The GVP volcano and eruption data derive both from the retrospective perspective of the volcanological and other literature and documentation of contemporary eruptions and volcanic unrest in the Smithsonian’s monthly bulletin and Weekly Volcanic Activity Reports compiled since 2000 in collaboration with the USGS.

EUROPEAN VOLCANOES' NIGHT: building a link between general public and volcanologists in a relaxed and welcoming setting

NASA Astrophysics Data System (ADS)

Calvo, David; González-Cárdenas, María E.; Baldrich, Laura; Solana, Carmen; Nave, Rosella; Calvari, Sonia; Harangi, Szabolcs; Chouraqui, Floriane; Dionis, Samara; Silva, Sonia V.; Forjaz, Victor H.; D'Auria, Luca; Pérez, Nemesio M.

2017-04-01

European Volcanoes' Night (www.volcanoesnight.com) is a "volcanic eruption" of art, culture, music, gastronomy, school activities, geotourism, exhibitions and scientific debates. The event aims to bring together members of the general public with scientists who work on the study of volcanoes, in order to meet and ask questions in a relaxed and welcoming setting. It is open to both locals and tourists who appreciate the beauty and power of this natural phenomena. This celebration gives attendees, and in particular young people, the opportunity to meet researchers in a relaxed and festive setting, which will feature many activities and which will be used to highlight the attractiveness of a career research on one of the most attractive natural phenomena; volcanoes. The 2016 European Volcanoes' Night was held at 16 different municipalities of Spain, France, Hungary, Italy, Portugal, United Kingdom and Cape Verde on September 30, 2016, coinciding with the celebration of "European Researchers' Night" held annually throughout Europe and neighbouring countries the last Friday of September. The spirit of the European VolcanoeśNight fits perfectly in the aim of the ERN, trying to close the gap between the scientific community and the rest of the society. In this case, volcanoes are the driving force of this event, celebrating the singularity of living on volcanoes, and how these affect our daily lives, our culture and our heritage. European VolcanoeśNight also celebrates volcano science, with avantgarde talks and presentations on different volcanic topics and becomes a meeting point for children discovering volcanoes as a pastime or a leisure topic, making this event a must for tourists and locals wherever has been held. At the end of 2016 European VolcanoeśNight, almost 150 activities were performed for thousands of spectators, a big success that confirms something as crucial as science as a communication issue, and as a tool to strengthen the ties between researchers and their communities. Now we are planning the 2017 European Volcanoes' Night and looking for additional institutions and municipalities to join this volcano adventure.

ICE-VOLC Project: unravelling the dynamics of Antarctica volcanoes

NASA Astrophysics Data System (ADS)

Cannata, Andrea; Del Carlo, Paola; Giudice, Gaetano; Giuffrida, Giovanni; Larocca, Graziano; Liuzzo, Marco

2017-04-01

Melbourne and Rittmann volcanoes are located in the Victoria Land. Whilst Rittmann's last eruption dates probably to Pleistocene, Melbourne's most recent eruption between 1862 and 1922, testifying it is still active. At present, both volcanoes display fumarolic activity. Melbourne was discovered in 1841 by James Clark Ross, Rittmann during the 4th Italian Expedition (1988/1989). Our knowledge on both volcanoes is really little. The position of these volcanoes in the Antarctic region (characterised by absence of anthropic noise) and its proximity with the Italian Mario Zucchelli Station makes them ideal sites for studying volcano seismic sources, geothermal emissions, seismo-acoustic signals caused by cryosphere-hydrosphere-atmosphere dynamics, and volcanic gas impact on environment. Hence, the main aim of the ICE-VOLC ("multiparametrIC Experiment at antarctica VOLCanoes: data from volcano and cryosphere-ocean-atmosphere dynamics") project is the study of Melbourne and Rittmann, by acquisition, analysis and integration of multiparametric geophysical, geochemical and thermal data. Complementary objectives include investigation of the relationship between seismo-acoustic activity recorded in Antarctica and cryosphere-hydrosphere-atmosphere dynamics, evaluation of the impact of volcanic gas in atmosphere. This project involves 26 researchers, technologists and technicians from University of Perugia and from Istituto Nazionale di Geofisica e Vulcanologia of Catania, Palermo, Pisa and Rome. In this work, we show the preliminary results obtained after the first expedition in Antarctica, aiming to perform geochemical-thermal surveys in the volcano ice caves, as well as to collect ash samples and to install temporary seismic stations.

Mt. St. Helens

NASA Technical Reports Server (NTRS)

2001-01-01

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

This 3-D anaglyph image of Mt. St. Helens volcano combines the nadir-looking and back-looking band 3 images of ASTER. To view the image in stereo, you will need blue-red glasses. Make sure to look through the red lens with your left eye. Figure 1: This ASTER image of Mt. St. Helens volcano in Washington was acquired on August 8, 2000 and covers an area of 37 by 51 km. Mount Saint Helens, a volcano in the Cascade Range of southwestern Washington that had been dormant since 1857, began to show signs of renewed activity in early 1980. On 18 May 1980, it erupted with such violence that the top of the mountain was blown off, spewing a cloud of ash and gases that rose to an altitude of 19 kilometers. The blast killed about 60 people and destroyed all life in an area of some 180 square kilometers (some 70 square miles), while a much larger area was covered with ash and debris. It continues to spit forth ash and steam intermittently. As a result of the eruption, the mountain's elevation decreased from 2,950 meters to 2,549 meters. The image is centered at 46.2 degrees north latitude, 122.2 degrees west longitude.

Movie: The simulated fly-over was produced by draping ASTER visible and near infrared image data over a digital topography model, created from ASTER's 3-D stereo bands. The color was computer enhanced to create a natural color image, where the vegetation appears green. The topography has been exaggerated 2 times to enhance the appearance of the relief.

The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate.

Subsurface Structure Interpretation Beneath of Mt. Pandan Based on Gravity Data

NASA Astrophysics Data System (ADS)

Santoso, D.; Wahyudi, E. J.; Alawiyah, S.; Nugraha, A. D.; Widiyantoro, S.; Kadir, W. G. A.; Supendi, P.; Wiyono, S.; Zulkafriza

2017-04-01

Mt. Pandan is one of the volcano that state as dormant volcano. On the other hand, Smyth et al. (2008) defined that Mt. Pandan is an active volcano. This volcano is apart a volcanic chain in Java island which is trending east-west along the island. This volcanic chain known as present day volcanic arc. Mt. Wilis is located in the south and it relatively much bigger compare to Mt. Pandan. There were earthquakes activity experienced in the surrounding Mt. Pandan area in the past several years. This event is interesting, because Mt. Pandan is not classify as the active volcano according to the list of volcanoes in Indonesia. On the otherhand Smyth et. al. (2008) mentioned that G. Pandan as modern volcanic which is located in Kendeng Zone of East Java. Gravity measurement around Mt. Pandan area was done in order to understand subsurface structure of Mt. Pandan. Gravity interpretation results shows that there is a low density structure beneath Mt. Pandan. It could be interpreted as existing of magma body below the surface. Some indication of submagmatic activities were found as hot spring and warm ground. Therefore it could be concluded that there is a possibility of magmatic activity below the Mt. Pandan.

Global data collection and the surveillance of active volcanoes

USGS Publications Warehouse

Ward, P.L.

1990-01-01

Data relay systems on existing earth-orbiting satellites provide an inexpensive way to collect environmental data from numerous remote sites around the world. This technology could be used effectively for fundamental monitoring of most of the world's active volcanoes. Such global monitoring would focus attention on the most dangerous volcanoes that are likely to significantly impact the geosphere and the biosphere. ?? 1990.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lagunova, I.A.

A characteristic feature of the products of mud-volcano activity in the Kerch-Taman region is their high boron content. Distribution of boron in waters of mud volcanoes is characterized by restriction of anomalously high concentrations of boron to mud volcanoes actively operating at the present time in general, and to the most active period of operation of the individual volcano; there is a direct correlation between boron and the hydrocarbonate ion (r/sub B//HCO/sub 3// = 0.5), and between boron and carbon dioxide from the mud-volcano gases (r/sub B//CO/sub 2// = 0.4). The correlation is lacking between boron and mineralization, and betweenmore » boron and chlorine, the correlation is close to inverse. A spatial connection between areas of development of mud volcanism and belts of boron mineralization has been established. Anomalously high boron concentrations in the products of mud volcanism in the Kerch-Taman region are part of the overall increased boron capacity of the Crimea and the Caucasus, which has been controlled by recent magmatic activity.« less

Klyuchevskaya, Volcano, Kamchatka Peninsula, CIS

NASA Image and Video Library

1991-05-06

STS039-77-010 (28 April 1991) --- The Kamchatka Peninsula, USSR. This oblique view of the eastern margin of the Kamchatka Peninsula shows pack-ice along the coast, which is drifting along with local currents and delineates the circulation patterns. Also visible are the Kamchatka River (left of center), and the volcanic complex with the active volcano Klyuchevskaya (Kloo-chevs'-ska-ya), 15,584 feet in elevation. The last reported eruption of the volcano was on April 8, but an ash and steam plume extending to the south can be seen in this photograph, taken almost three weeks later (April 28). On April 29, the crew observed and photographed the volcano again, and it was no longer visibly active. However, the flanks of the mountain are dirty from the ash fall. Just north of the Kamchatka River (to the left, just off frame) is Shiveluch, a volcano which was active in early April. There are more than 100 volcanic edifices recognized on Kamchatka, with 15 classified as active.

Using near-real-time monitoring data from Pu'u 'Ō'ō vent at Kīlauea Volcano for training and educational purposes

USGS Publications Warehouse

Teasdale, Rachel; Kraft, Katrien van der Hoeven; Poland, Michael P.

2015-01-01

Training non-scientists in the use of volcano-monitoring data is critical preparation in advance of a volcanic crisis, but it is currently unclear which methods are most effective for improving the content-knowledge of non-scientists to help bridge communications between volcano experts and non-experts. We measured knowledge gains for beginning-(introductory-level students) and novice-level learners (students with a basic understanding of geologic concepts) engaged in the Volcanoes Exploration Program: Pu‘u ‘Ō‘ō (VEPP) “Monday Morning Meeting at the Hawaiian Volcano Observatory” classroom activity that incorporates authentic Global Positioning System (GPS), tilt, seismic, and webcam data from the Pu‘u ‘Ō‘ō eruptive vent on Kīlauea Volcano, Hawai‘i (NAGT website, 2010), as a means of exploring methods for effectively advancing non-expert understanding of volcano monitoring. Learner groups consisted of students in introductory and upper-division college geology courses at two different institutions. Changes in their content knowledge and confidence in the use of data were assessed before and after the activity using multiple-choice and open-ended questions. Learning assessments demonstrated that students who took part in the exercise increased their understanding of volcano-monitoring practices and implications, with beginners reaching a novice stage, and novices reaching an advanced level (akin to students who have completed an upper-division university volcanology class). Additionally, participants gained stronger confidence in their ability to understand the data. These findings indicate that training modules like the VEPP: Monday Morning Meeting classroom activity that are designed to prepare non-experts for responding to volcanic activity and interacting with volcano scientists should introduce real monitoring data prior to proceeding with role-paying scenarios that are commonly used in such courses. The learning gains from the combined approach will help improve effective communications between volcano experts and non-experts during times of crisis, thereby reducing the potential for confusion and misinterpretation of data.

Sheveluch Volcano, Kamchatka, Russia

NASA Image and Video Library

2010-04-05

Sheveluch Volcano in Kamchatka, Siberia, is one of the frequently active volcanoes located in eastern Siberia. In this image from NASA Terra spacecraft, brownish ash covers the southern part of the mountain, under an ash-laden vertical eruption plume.

Catalog of earthquake hypocenters at Alaskan volcanoes: January 1 through December 31, 2002

USGS Publications Warehouse

Dixon, James P.; Stihler, Scott D.; Power, John A.; Tytgat, Guy; Moran, Seth C.; Sánchez, John; Estes, Steve; McNutt, Stephen R.; Paskievitch, John

2003-01-01

The Alaska Volcano Observatory (AVO), a cooperative program of the U.S. Geological Survey, the Geophysical Institute of the University of Alaska Fairbanks, and the Alaska Division of Geological and Geophysical Surveys, has maintained seismic monitoring networks at historically active volcanoes in Alaska since 1988 (Power and others, 1993; Jolly and others, 1996; Jolly and others, 2001; Dixon and others, 2002). The primary objectives of this program are the seismic monitoring of active, potentially hazardous, Alaskan volcanoes and the investigation of seismic processes associated with active volcanism. This catalog presents the basic seismic data and changes in the seismic monitoring program for the period January 1, 2002 through December 31, 2002. Appendix G contains a list of publications pertaining to seismicity of Alaskan volcanoes based on these and previously recorded data. The AVO seismic network was used to monitor twenty-four volcanoes in real time in 2002. These include Mount Wrangell, Mount Spurr, Redoubt Volcano, Iliamna Volcano, Augustine Volcano, Katmai Volcanic Group (Snowy Mountain, Mount Griggs, Mount Katmai, Novarupta, Trident Volcano, Mount Mageik, Mount Martin), Aniakchak Crater, Mount Veniaminof, Pavlof Volcano, Mount Dutton, Isanotski Peaks, Shishaldin Volcano, Fisher Caldera, Westdahl Peak, Akutan Peak, Makushin Volcano, Great Sitkin Volcano, and Kanaga Volcano (Figure 1). Monitoring highlights in 2002 include an earthquake swarm at Great Sitkin Volcano in May-June; an earthquake swarm near Snowy Mountain in July-September; low frequency (1-3 Hz) tremor and long-period events at Mount Veniaminof in September-October and in December; and continuing volcanogenic seismic swarms at Shishaldin Volcano throughout the year. Instrumentation and data acquisition highlights in 2002 were the installation of a subnetwork on Okmok Volcano, the establishment of telemetry for the Mount Veniaminof subnetwork, and the change in the data acquisition system to an EARTHWORM detection system. AVO located 7430 earthquakes during 2002 in the vicinity of the monitored volcanoes. This catalog includes: (1) a description of instruments deployed in the field and their locations; (2) a description of earthquake detection, recording, analysis, and data archival systems; (3) a description of velocity models used for earthquake locations; (4) a summary of earthquakes located in 2002; and (5) an accompanying UNIX tar-file with a summary of earthquake origin times, hypocenters, magnitudes, and location quality statistics; daily station usage statistics; and all HYPOELLIPSE files used to determine the earthquake locations in 2002.The AVO seismic network was used to monitor twenty-four volcanoes in real time in 2002. These include Mount Wrangell, Mount Spurr, Redoubt Volcano, Iliamna Volcano, Augustine Volcano, Katmai Volcanic Group (Snowy Mountain, Mount Griggs, Mount Katmai, Novarupta, Trident Volcano, Mount Mageik, Mount Martin), Aniakchak Crater, Mount Veniaminof, Pavlof Volcano, Mount Dutton, Isanotski Peaks, Shishaldin Volcano, Fisher Caldera, Westdahl Peak, Akutan Peak, Makushin Volcano, Great Sitkin Volcano, and Kanaga Volcano (Figure 1). Monitoring highlights in 2002 include an earthquake swarm at Great Sitkin Volcano in May-June; an earthquake swarm near Snowy Mountain in July-September; low frequency (1-3 Hz) tremor and long-period events at Mount Veniaminof in September-October and in December; and continuing volcanogenic seismic swarms at Shishaldin Volcano throughout the year. Instrumentation and data acquisition highlights in 2002 were the installation of a subnetwork on Okmok Volcano, the establishment of telemetry for the Mount Veniaminof subnetwork, and the change in the data acquisition system to an EARTHWORM detection system. AVO located 7430 earthquakes during 2002 in the vicinity of the monitored volcanoes.This catalog includes: (1) a description of instruments deployed in the field and their locations; (2) a description of earthquake detection, recording, analysis, and data archival systems; (3) a description of velocity models used for earthquake locations; (4) a summary of earthquakes located in 2002; and (5) an accompanying UNIX tar-file with a summary of earthquake origin times, hypocenters, magnitudes, and location quality statistics; daily station usage statistics; and all HYPOELLIPSE files used to determine the earthquake locations in 2002.

Database for the Geologic Map of Newberry Volcano, Deschutes, Klamath, and Lake Counties, Oregon

USGS Publications Warehouse

Bard, Joseph A.; Ramsey, David W.; MacLeod, Norman S.; Sherrod, David R.; Chitwood, Lawrence A.; Jensen, Robert A.

2013-01-01

Newberry Volcano, one of the largest Quaternary volcanoes in the conterminous United States, is a broad shield-shaped volcano measuring 60 km north-south by 30 km east-west with a maximum elevation of more than 2 km. Newberry Volcano is the product of deposits from thousands of eruptions, including at least 25 in the past approximately 12,000 years (Holocene Epoch). Newberry Volcano has erupted as recently as 1,300 years ago, but isotopic ages indicate that the volcano began its growth as early as 0.6 million years ago. Such a long eruptive history and recent activity suggest that Newberry Volcano is likely to erupt in the future. This geologic map database of Newberry Volcano distinguishes rocks and deposits based on their composition, age, and lithology.

Historic volcanology document reprinted

NASA Astrophysics Data System (ADS)

Fiske, Richard S.

On the occasion of the 75th anniversary of the founding of the Hawaiian Volcano Observatory (HVO), the Smithsonian Institution (Washington, D.C.) has reprinted an historic, hard-to-find reference on volcanic activity in Hawaii and around the world that was published at the observatory from 1925 to 1955. The Volcano Letter contains the definitive reports of many Hawaiian eruptions, such as activity in Halemaumau at Kilauea from the late 1920s to 1934 and the Mauna Loa eruptions of 1935 and the 1940s; accounts of the development of volcano-monitoring techniques at HVO; scholarly reports on historic activity at volcanos in Hawaii and around the world; and reports of seismicity in Hawaii and elsewhere.

Spreading And Collapse Of Big Basaltic Volcanoes

NASA Astrophysics Data System (ADS)

Puglisi, G.; Bonforte, A.; Guglielmino, F.; Peltier, A.; Poland, M. P.

2015-12-01

Among the different types of volcanoes, basaltic ones usually form the most voluminous edifices. Because volcanoes are growing on a pre-existing landscape, the geologic and structural framework of the basement (and earlier volcanic landforms) influences the stress regime, seismicity, and volcanic activity. Conversely, the masses of these volcanoes introduce a morphological anomaly that affects neighboring areas. Growth of a volcano disturbs the tectonic framework of the region, clamps and unclamps existing faults (some of which may be reactivated by the new stress field), and deforms the substratum. A volcano's weight on its basement can trigger edifice spreading and collapse that can affect populated areas even at significant distance. Volcano instability can also be driven by slow tectonic deformation and magmatic intrusion. The manifestations of instability span a range of temporal and spatial scales, ranging from slow creep on individual faults to large earthquakes affecting a broad area. Our work aims to investigate the relation between basement setting and volcanic activity and stability at Etna (Sicily, Italy), Kilauea (Island of Hawaii, USA) and Piton de la Fournaise (La Reunion Island, France). These volcanoes host frequent eruptive activity (effusive and explosive) and share common features indicating lateral spreading and collapse, yet they are characterized by different morphologies, dimensions, and tectonic frameworks. For instance, the basaltic ocean island volcanoes of Kilauea and Piton de la Fournaise are near the active ends of long hotspot chains while Mt. Etna has developed at junction along a convergent margin between the African and Eurasian plates and a passive margin separating the oceanic Ionian crust from the African continental crust. Magma supply and plate velocity also differ in the three settings, as to the sizes of the edifices and the extents of their rift zones. These volcanoes, due to their similarities and differences, coupled with their long-time and high-level monitoring networks, represent the best natural laboratories for investigating the manifestations and mechanisms of spreading and collapse, the feedback process between spreading and eruptive activity (especially along rift zones), and the role of the regional geodynamics.

Single-station monitoring of volcanoes using seismic ambient noise

NASA Astrophysics Data System (ADS)

De Plaen, Raphael S. M.; Lecocq, Thomas; Caudron, Corentin; Ferrazzini, Valérie; Francis, Olivier

2016-08-01

Seismic ambient noise cross correlation is increasingly used to monitor volcanic activity. However, this method is usually limited to volcanoes equipped with large and dense networks of broadband stations. The single-station approach may provide a powerful and reliable alternative to the classical "cross-station" approach when measuring variation of seismic velocities. We implemented it on the Piton de la Fournaise in Reunion Island, a very active volcano with a remarkable multidisciplinary continuous monitoring. Over the past decade, this volcano has been increasingly studied using the traditional cross-correlation technique and therefore represents a unique laboratory to validate our approach. Our results, tested on stations located up to 3.5 km from the eruptive site, performed as well as the classical approach to detect the volcanic eruption in the 1-2 Hz frequency band. This opens new perspectives to successfully forecast volcanic activity at volcanoes equipped with a single three-component seismometer.

Remote sensing of volcanos and volcanic terrains

NASA Technical Reports Server (NTRS)

Mouginis-Mark, Peter J.; Francis, Peter W.; Wilson, Lionel; Pieri, David C.; Self, Stephen; Rose, William I.; Wood, Charles A.

1989-01-01

The possibility of using remote sensing to monitor potentially dangerous volcanoes is discussed. Thermal studies of active volcanoes are considered along with using weather satellites to track eruption plumes and radar measurements to study lava flow morphology and topography. The planned use of orbiting platforms to study emissions from volcanoes and the rate of change of volcanic landforms is considered.

Earth Observations by the Expedition 19 crew

NASA Image and Video Library

2009-04-08

ISS019-E-005286 (8 April 2009) --- Mount Fuji, Japan is featured in this image photographed by an Expedition 19 crew member on the International Space Station. The 3,776 meters high Mount Fuji volcano, located on the island of Honshu in Japan, is one of the world?s classic examples of a stratovolcano. The volcano?s steep, conical profile is the result of numerous interlayered lava flows and explosive eruption products ? such as ash, cinders, and volcanic bombs ? building up the volcano over time. The steep profile is possible because of the relatively high viscosity of the volcanic rocks typically associated with stratovolcanoes. This leads to thick sequences of lava flows near the eruptive vent that build the cone structure, rather than low viscosity flows that spread out over the landscape and build lower-profile shield volcanoes. According to scientists, Mount Fuji, or Fuji-san in Japan, is actually comprised of several overlapping volcanoes that began erupting in the Pleistocene Epoch (1.8 million to approximately 10,000 years ago). Scientists believe that the currently active volcano, known as Younger Fuji, began forming approximately 11,000 to 8,000 years ago. The most recent explosive activity occurred in 1707, creating Hoei Crater on the southeastern flank of the volcano (center). This eruption deposited ash on Edo (present-day Tokyo) located 95 kilometers to the northeast. While there have been no further eruptions of Mount Fuji, steam was observed at the summit during 1780?1820, and the volcano is considered active. This oblique photograph illustrates the snow-covered southeastern flank of the volcano; the northeastern flank can be seen here. A representation of the topography of Mt. Fuji and its surroundings can be viewed here.

Testing a New Method for Imaging Crustal Magma Bodies: A Pilot Study at Newberry Volcano, Central OR

NASA Astrophysics Data System (ADS)

Beachly, M. W.; Hooft, E. E.; Toomey, D. R.; Waite, G. P.; Durant, D. T.

2010-12-01

Magmatic systems are often imaged using delay time seismic tomography, though a known limitation is that wavefront healing limits the ability of transmitted waves to detect small, low-velocity regions such as magma chambers. Crustal magma chambers have been successfully identified using secondary arrivals, including both P and S wave reflections and conversions. Such secondary phases are often recorded by marine seismic experiments owing to the density and quality of airgun data, which improves the identification of coherent arrivals. In 2008 we conducted a pilot study at Newberry volcano to test a new method of detecting secondary arrivals in a terrestrial setting. Our experimental geometry used a line of densely spaced (~300 m), three-component seismometers to record a shot-of-opportunity from the High Lave Plains Experiment. An ideal study would record several shots, however, data from this single event proves the concept. As part of our study, we also reanalyze all existing seismic data from Newberry volcano to obtain a tomographic image of the velocity structure to 6 km depth. Newberry is a lone shield volcano in central Oregon, located 40 km east of the Cascade axis. Newberry eruptions are silicic within the central caldera and mafic on its periphery suggesting a central silicic magma storage system, possibly located at upper crustal depths. The system may still be active with a recent eruption ~1300 years ago, and a central drill hole temperature of 256° C at only 932 m depth. A low-velocity anomaly previously imaged at 3-5 km beneath the caldera indicates either a magma body or a fractured pluton. Our tomographic study combines our 2008 seismic data with profile and array data collected in the 1980s by the USGS. In total, the inversion includes 16 active sources and 322 receivers yielding 1007 P-wave first arrivals. Beneath the caldera ring faults we image a high-velocity ring-like anomaly extending to 2 km depth. This anomaly is inferred to be near-vertical ring-dikes, 200-500 m thick, that resulted from caldera formation 5 mya. Low velocities imaged within the ring are attributed to caldera fill. Below 2.5 km depth a pair of high velocity bodies may be solidified intrusive complexes east and west of the caldera. Our results also indicate a low velocity body between 4-6 km depth although it is poorly resolved by delay time data. Tomographic inversions of synthetic data suggest that the observed travel times are consistent with a low-velocity body up to 35 km3 with up to 40% velocity reduction. Using data from our densely instrumented 2008 seismic profile, we identify a secondary P-wave arrival that originates from beneath the caldera. Preliminary finite-difference waveform modeling produces a similar arrival for a model including a low-velocity body with a 2-km-long melt sill at 3 km depth underlain by a partial-melt region to 5 km depth. The secondary arrival provides additional evidence for an active crustal magmatic system beneath Newberry volcano and demonstrates the potential of novel experimental geometries for detecting and locating terrestrial crustal magma bodies.

NASA Spacecraft Captures Fury of Russian Volcano

NASA Image and Video Library

2011-01-27

This nighttime thermal infrared image from NASA Terra spacecraft shows Shiveluch volcano, one of the largest and most active volcanoes in Russia Kamchatka Peninsula; the bright, hot summit lava dome is evident in the center of the image.

Special issue: The changing shapes of active volcanoes: Recent results and advances in volcano geodesy

USGS Publications Warehouse

Poland, Michael P.; Newman, Andrew V.

2006-01-01

The 18 papers herein report on new geodetic data that offer valuable insights into eruptive activity and magma transport; they present new models and modeling strategies that have the potential to greatly increase understanding of magmatic, hydrothermal, and volcano-tectonic processes; and they describe innovative techniques for collecting geodetic measurements from remote, poorly accessible, or hazardous volcanoes. To provide a proper context for these studies, we offer a short review of the evolution of volcano geodesy, as well as a case study that highlights recent advances in the field by comparing the geodetic response to recent eruptive episodes at Mount St. Helens. Finally, we point out a few areas that continue to challenge the volcano geodesy community, some of which are addressed by the papers that follow and which undoubtedly will be the focus of future research for years to come.

The threat of silent earthquakes

USGS Publications Warehouse

Cervelli, Peter

2004-01-01

Not all earthquakes shake the ground. The so-called silent types are forcing scientists to rethink their understanding of the way quake-prone faults behave. In rare instances, silent earthquakes that occur along the flakes of seaside volcanoes may cascade into monstrous landslides that crash into the sea and trigger towering tsunamis. Silent earthquakes that take place within fault zones created by one tectonic plate diving under another may increase the chance of ground-shaking shocks. In other locations, however, silent slip may decrease the likelihood of destructive quakes, because they release stress along faults that might otherwise seem ready to snap.

Landslide Hazards in the Seattle, Washington, Area

USGS Publications Warehouse

Baum, Rex; Harp, Ed; Highland, Lynn

2007-01-01

The Seattle, Washington, area is known for its livability and its magnificent natural setting. The city and nearby communities are surrounded by an abundance of rivers and lakes and by the bays of Puget Sound. Two majestic mountain ranges, the Olympics and the Cascades, rim the region. These dramatic natural features are products of dynamic forces-landslides, earthquakes, tsunamis, glaciers, volcanoes, and floods. The same processes that formed this beautiful landscape pose hazards to the ever-growing population of the region. Landslides long have been a major cause of damage and destruction to people and property in the Seattle area.

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

NASA Astrophysics Data System (ADS)

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

2008-12-01

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

The Anatahan volcano-monitoring system

NASA Astrophysics Data System (ADS)

Marso, J. N.; Lockhart, A. B.; White, R. A.; Koyanagi, S. K.; Trusdell, F. A.; Camacho, J. T.; Chong, R.

2003-12-01

A real-time 24/7 Anatahan volcano-monitoring and eruption detection system is now operational. There had been no real-time seismic monitoring on Anatahan during the May 10, 2003 eruption because the single telemetered seismic station on Anatahan Island had failed. On May 25, staff from the Emergency Management Office (EMO) of the Commonwealth of the Northern Mariana Islands and the U. S. Geological Survey (USGS) established a replacement telemetered seismic station on Anatahan whose data were recorded on a drum recorder at the EMO on Saipan, 130 km to the south by June 5. In late June EMO and USGS staff installed a Glowworm seismic data acquisition system (Marso et al, 2003) at EMO and hardened the Anatahan telemetry links. The Glowworm system collects the telemetered seismic data from Anatahan and Saipan, places graphical display products on a webpage, and exports the seismic waveform data in real time to Glowworm systems at Hawaii Volcano Observatory and Cascades Volcano Observatory (CVO). In early July, a back-up telemetered seismic station was placed on Sarigan Island 40 km north of Anatahan, transmitting directly to the EMO on Saipan. Because there is currently no population on the island, at this time the principal hazard presented by Anatahan volcano would be air traffic disruption caused by possible erupted ash. The aircraft/ash hazard requires a monitoring program that focuses on eruption detection. The USGS currently provides 24/7 monitoring of Anatahan with a rotational seismic duty officer who carries a Pocket PC-cell phone combination that receives SMS text messages from the CVO Glowworm system when it detects large seismic signals. Upon receiving an SMS text message notification from the CVO Glowworm, the seismic duty officer can use the Pocket PC - cell phone to view a graphic of the seismic traces on the EMO Glowworm's webpage to determine if the seismic signal is eruption related. There have been no further eruptions since the monitoring system was installed, but regional tectonic earthquakes have provided frequent tests of the system. Reliance on a Pocket PC - cell phone requires that the seismic duty officer remain in an area with cell phone coverage. With this monitoring method, the USGS is able to provide rapid notice of an Anatahan eruption to the EMO and the Washington Volcano Ash Advisory Center. Reference Marso, J.N., Murray, T.L., Lockhart, A.B., Bryan, C.J., Glowworm: An extended PC-based Earthworm system for volcano monitoring. Abstracts, Cities On Volcanoes III, Hilo Hawaii, July 2003.

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

NASA Astrophysics Data System (ADS)

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.

Stratigraphy of Late Pleistocene-Holocene pyroclastic deposits of Tacana Volcano, Mexico-Guatemala

NASA Astrophysics Data System (ADS)

Macias, J. L.; Arce, J. L.; Garcia-Palomo, A.; Mora, J. C.; Saucedo, R.; Hughes, S.; Scolamacchia, T.

2005-12-01

Tacana volcano (4,060 masl), the highest peak of the Tacana Volcanic Complex, is an acitve volcano located on the Mexico-Guatemala border. Tacana resumed phreatic activity in 1950 and again in 1986. After this last event, the volcano became the locus of attention of authorities and local scientists began to study the complex. Tacana's stratigraphic record has been studied using radiocarbon dating and these indicate that the volcano has been very active in the past producing at least 12 explosive eruptions during the last 40 ka years as follow: a) Four partial dome destruction events with the generation of block-and-ash flow deposits at 40, 28, <26, and 16 ka. b) Four small-volume phreatomagmatic events that emplaced dilute density currents at 10.6, 7.5, 6, and 2.5 ka. c) Four eruptions that emplaced pumice-rich fall deposits, three of them widely dispersed towards the NE flank of the volcano in Guatemala and dated at ~32, <24 and <14 ka, and finally a 0.8 ka fall deposit restricted to the crater vicinity that might represent the youngest magmatic eruption of the volcano. Although refining of these stratigraphic sequence is still underway, the eruptive chronology of Tacana volcano cleary indicates that explosive eruptions producing plinian fall and pyroclastic density currents have taken place every 1 to 8 ka years. This record constrasts with the small phreatic eruptions that occur 1-2 per century. So, this indicates that Tacana volcano is more active than previously considered and these results must be considered for future researches on hazards maps and mitigation.

The Keelung Submarine volcanoes and gas plumes in the nearshore of northern Taiwan

NASA Astrophysics Data System (ADS)

Huang, J. C.; Tsia, C. H.; Hsu, S. K.; Lin, S. S.

2016-12-01

Taiwan is located in the collision zone between Philippine Sea Plate and Eurasian Plate. The Philippine Sea Plate subducts northward beneath the Ryukyu arc system while the Eurasian Plate subducts eastward beneath the Luzon arc system. The Taiwan mountain building started at 9 My ago and the most active collision has migrated to middle Taiwan. In consequence, the northern Taiwan has changed its stress pattern from forms a series of thrust faults to normal faults. The stress pattern change has probably induced the post-collisional extension and volcanism in and off northern Taiwan. Under such a tectonic environment, the volcanism and gas plumes are widespread in northern Taiwan and its offshore area. Among the volcanoes of the northern Taiwan volcanic zone, the Tatun Volcano Group is the most obvious one. In this study, we use sub-bottom profiler, EK500 echo sounder, and multibeam echo sounder to study the geophysical structure of a submarine volcano in the nearshore of northern Taiwan. We have analyzed the shallow structures and identified the locations of the gas plumes. The identification of the gas plumes can help us understand the nature of the submarine volcano. Our results show that the gas plumes appear near the Kanchiao Fault and Keelung islet. Some intrusive volcanoes can be observed in the subbottom profiler data. Finally, according to the observations, we found that the Keelung Submarine Volcano is still active. We need the monitor of the active Keelung Submarine Volcano to avoid the volcanic hazard. Additionally, we need to pay attention to the earthquakes related to the Keelung Submarine Volcano.

Earth Observations taken by the Expedition 18 Crew

NASA Image and Video Library

2009-02-24

ISS018-E-035716 (24 Feb. 2009) --- Minchinmavida and Chaiten Volcanoes in Chile are featured in this image photographed by an Expedition 18 crewmember on the International Space Station. The Andes mountain chain along the western coastline of South America includes numerous active stratovolcanoes. The majority of these volcanoes are formed, and fed, by magma generated as the oceanic Nazca tectonic plate moves northeastward and plunges beneath the less dense South American continental tectonic plate (a process known as subduction). The line of Andean volcanoes marks the approximate location of the subduction zone. This astronaut photograph highlights two volcanoes located near the southern boundary of the Nazca ? South America subduction zone in southern Chile. Dominating the scene is the massive Minchinmavida stratovolcano at center. An eruption of this glaciated volcano was observed by Charles Darwin during his Galapagos Island voyage in 1834; the last recorded eruption took place the following year. The white, snow covered summit of Minchinmavida is blanketed by gray ash erupted from its much smaller but now active neighbor to the west, Volcan (volcano) Chaiten. The historically inactive Chaiten volcano, characterized by a large lava dome within a caldera (an emptied and collapsed magma chamber beneath a volcano) roared back to life unexpectedly on May 2, 2008, generating dense ash plumes and forcing the evacuation of the nearby town of Chaiten. Volcanic activity continues at Chaiten, including partial collapse of a new lava dome and generation of a pyroclastic flow several days before this photograph was taken. A steam and ash plume is visible extending to the northeast from the eruptive center of the volcano.

San Miguel Volcanic Seismic and Structure in Central America: Insight into the Physical Processes of Volcanoes

NASA Astrophysics Data System (ADS)

Patlan, E.; Velasco, A.; Konter, J. G.

2010-12-01

The San Miguel volcano lies near the city of San Miguel, El Salvador (13.43N and - 88.26W). San Miguel volcano, an active stratovolcano, presents a significant natural hazard for the city of San Miguel. In general, the internal state and activity of volcanoes remains an important component to understanding volcanic hazard. The main technology for addressing volcanic hazards and processes is through the analysis of data collected from the deployment of seismic sensors that record ground motion. Six UTEP seismic stations were deployed around San Miguel volcano from 2007-2008 to define the magma chamber and assess the seismic and volcanic hazard. We utilize these data to develop images of the earth structure beneath the volcano, studying the volcanic processes by identifying different sources, and investigating the role of earthquakes and faults in controlling the volcanic processes. We initially locate events using automated routines and focus on analyzing local events. We then relocate each seismic event by hand-picking P-wave arrivals, and later refine these picks using waveform cross correlation. Using a double difference earthquake location algorithm (HypoDD), we identify a set of earthquakes that vertically align beneath the edifice of the volcano, suggesting that we have identified a magma conduit feeding the volcano. We also apply a double-difference earthquake tomography approach (tomoDD) to investigate the volcano’s plumbing system. Our preliminary results show the extent of the magma chamber that also aligns with some horizontal seismicity. Overall, this volcano is very active and presents a significant hazard to the region.

NASA Satellite Images Erupting Russian Volcano

NASA Image and Video Library

2017-08-22

Klyuchevskoi, one of the world's most active volcanoes, is seen poking through above a solid cloud deck, with an ash plume streaming to the west. Located on the Kamchatka Peninsula in far eastern Russia, it is one of many active volcanoes on the Peninsula. Nearby, to the south, the smaller Bezymianny volcano can be seem with a small steam plume coming from its summit. The image was acquired Aug. 20, 2017, covers an area of 12 by 14 miles (19.5 by 22.7 kilometers), and is located at 56.1 degrees north, 160.6 degrees east. https://photojournal.jpl.nasa.gov/catalog/PIA21878

Methanogenic diversity and activity in hypersaline sediments of the centre of the Napoli mud volcano, Eastern Mediterranean Sea.

PubMed

Lazar, Cassandre Sara; Parkes, R John; Cragg, Barry A; L'Haridon, Stéphane; Toffin, Laurent

2011-08-01

Submarine mud volcanoes are a significant source of methane to the atmosphere. The Napoli mud volcano, situated in the brine-impacted Olimpi Area of the Eastern Mediterranean Sea, emits mainly biogenic methane particularly at the centre of the mud volcano. Temperature gradients support the suggestion that Napoli is a cold mud volcano with moderate fluid flow rates. Biogeochemical and molecular genetic analyses were carried out to assess the methanogenic activity rates, pathways and diversity in the hypersaline sediments of the centre of the Napoli mud volcano. Methylotrophic methanogenesis was the only significant methanogenic pathway in the shallow sediments (0-40 cm) but was also measured throughout the sediment core, confirming that methylotrophic methanogens could be well adapted to hypersaline environments. Hydrogenotrophic methanogenesis was the dominant pathway below 50 cm; however, low rates of acetoclastic methanogenesis were also present, even in sediment layers with the highest salinity, showing that these methanogens can thrive in this extreme environment. PCR-DGGE and methyl coenzyme M reductase gene libraries detected sequences affiliated with anaerobic methanotrophs (mainly ANME-1) as well as Methanococcoides methanogens. Results show that the hypersaline conditions in the centre of the Napoli mud volcano influence active biogenic methane fluxes and methanogenic/methylotrophic diversity. © 2011 Society for Applied Microbiology and Blackwell Publishing Ltd.

Evaluating life-safety risk of fieldwork at New Zealand's active volcanoes

NASA Astrophysics Data System (ADS)

Deligne, Natalia; Jolly, Gill; Taig, Tony; Webb, Terry

2014-05-01

Volcano observatories monitor active or potentially active volcanoes. Although the number and scope of remote monitoring instruments and methods continues to grow, in-person field data collection is still required for comprehensive monitoring. Fieldwork anywhere, and especially in mountainous areas, contains an element of risk. However, on volcanoes with signs of unrest, there is an additional risk of volcanic activity escalating while on site, with potentially lethal consequences. As an employer, a volcano observatory is morally and sometimes legally obligated to take reasonable measures to ensure staff safety and to minimise occupational risk. Here we present how GNS Science evaluates life-safety risk for volcanologists engaged in fieldwork on New Zealand volcanoes with signs of volcanic unrest. Our method includes several key elements: (1) an expert elicitation for how likely an eruption is within a given time frame, (2) quantification of, based on historical data when possible, given a small, moderate, or large eruption, the likelihood of exposure to near-vent processes, ballistics, or surge at various distances from the vent, and (3) estimate of fatality rate given exposure to these volcanic hazards. The final product quantifies hourly fatality risk at various distances from a volcanic vent; various thresholds of risk (for example, zones with more than 10-5 hourly fatality risk) trigger different levels of required approval to undertake work. Although an element of risk will always be present when conducting fieldwork on potentially active volcanoes, this is a first step towards providing objective guidance for go/no go decisions for volcanic monitoring.

Reducing Disaster Vulnerability Through Science and Technology

DTIC Science & Technology

2003-07-01

engineering design. Source: “Massive Alaska Earthquake Rocks the Mainland,” Volcano Watch, Hawaiian Volcano Observatory, November 14, 2002, http... volcanoes , and landslides ■ Disease epidemics ■ Technological disasters, including critical infrastructure threats, oil and chemical spills, and building...risk reduction can enhance protection of buildings even in these high-risk areas. Volcanoes The United States is among the most volcanically active

Activity at Europe Most Active Volcano Eyed by NASA Spacecraft

NASA Image and Video Library

2016-05-27

Mt. Etna, Sicily, Italy, is Europe most active volcano. In mid-May 2016, Mt. Etna put on a display of lava fountaining, ash clouds and lava flows. Three of the four summit craters were active. NASA Terra spacecraft acquired this image on May 26, 2016.

Seismicity at Fuego, Pacaya, Izalco, and San Cristobal Volcanoes, Central America, 1973-1974

USGS Publications Warehouse

McNutt, S.R.; Harlow, D.H.

1983-01-01

Seismic data collected at four volcanoes in Central America during 1973 and 1974 indicate three sources of seismicity: regional earthquakes with hypocentral distances greater than 80 km, earthquakes within 40 km of each volcano, and seismic activity originating at the volcanoes due to eruptive processes. Regional earthquakes generated by the underthrusting and subduction of the Cocos Plate beneath the Caribbean Plate are the most prominent seismic feature in Central America. Earthquakes in the vicinity of the volcanoes occur on faults that appear to be related to volcano formation. Faulting near Fuego and Pacaya volcanoes in Guatemala is more complex due to motion on a major E-W striking transform plate boundary 40 km north of the volcanoes. Volcanic activity produces different kinds of seismic signatures. Shallow tectonic or A-type events originate on nearby faults and occur both singly and in swarms. There are typically from 0 to 6 A-type events per day with b value of about 1.3. At very shallow depths beneath Pacaya, Izalco, and San Cristobal large numbers of low-frequency or B-type events are recorded with predominant frequencies between 2.5 and 4.5 Hz and with b values of 1.7 to 2.9. The relative number of B-type events appears to be related to the eruptive states of the volcanoes; the more active volcanoes have higher levels of seismicity. At Fuego Volcano, however, low-frequency events have unusually long codas and appear to be similar to tremor. High-amplitude volcanic tremor is recorded at Fuego, Pacaya, and San Cristobal during eruptive periods. Large explosion earthquakes at Fuego are well recorded at five stations and yield information on near-surface seismic wave velocities (??=3.0??0.2 km/sec.). ?? 1983 Intern. Association of Volcanology and Chemistry of the Earth's Interior.

Environmental Impact Analysis Process. Preliminary Environmental Constraints Survey U.S. Air Force, Space Division Advanced Launch System (ALS)

DTIC Science & Technology

1988-09-01

of Mauna Loa and Kilauea volcanoes . Both are shield volcanoes , having a broad summit and base. The southeastern flanks of the volcanoes are riddled...potential of volcanic activity (Telling, et al. 1987). Lava flows from the Kilauea volcano frequently inundate the area a few miles north of Palima Point...The Hawaii Volcanoes National Park, which is between 1.5 and 25 miles from the proposed project sites, has been designated as a Class I area by the

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

USGS Publications Warehouse

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

2014-01-01

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

Tweed Extinct Volcano, Australia, Stereo Pair of SRTM Shaded Relief and Colored Height

NASA Image and Video Library

2005-01-06

Australia is the only continent without any current volcanic activity, but it hosts one of the world largest extinct volcanoes, the Tweed Volcano. Rock dating methods indicate that eruptions here lasted about three million years.

Novel microbial communities of the Haakon Mosby mud volcano and their role as a methane sink.

PubMed

Niemann, Helge; Lösekann, Tina; de Beer, Dirk; Elvert, Marcus; Nadalig, Thierry; Knittel, Katrin; Amann, Rudolf; Sauter, Eberhard J; Schlüter, Michael; Klages, Michael; Foucher, Jean Paul; Boetius, Antje

2006-10-19

Mud volcanism is an important natural source of the greenhouse gas methane to the hydrosphere and atmosphere. Recent investigations show that the number of active submarine mud volcanoes might be much higher than anticipated (for example, see refs 3-5), and that gas emitted from deep-sea seeps might reach the upper mixed ocean. Unfortunately, global methane emission from active submarine mud volcanoes cannot be quantified because their number and gas release are unknown. It is also unclear how efficiently methane-oxidizing microorganisms remove methane. Here we investigate the methane-emitting Haakon Mosby Mud Volcano (HMMV, Barents Sea, 72 degrees N, 14 degrees 44' E; 1,250 m water depth) to provide quantitative estimates of the in situ composition, distribution and activity of methanotrophs in relation to gas emission. The HMMV hosts three key communities: aerobic methanotrophic bacteria (Methylococcales), anaerobic methanotrophic archaea (ANME-2) thriving below siboglinid tubeworms, and a previously undescribed clade of archaea (ANME-3) associated with bacterial mats. We found that the upward flow of sulphate- and oxygen-free mud volcano fluids restricts the availability of these electron acceptors for methane oxidation, and hence the habitat range of methanotrophs. This mechanism limits the capacity of the microbial methane filter at active marine mud volcanoes to <40% of the total flux.

Seismic and deformation precursory to the small explosions of Marapi Volcano, West Sumatra, Indonesia

NASA Astrophysics Data System (ADS)

Hidayat, D.; Patria, C.; Gunawan, H.; Taisne, B.; Nurfiani, D.; Avila, E. J.

2015-12-01

Marapi Volcano is one of the active volcanoes of Indonesia located near the city of Bukittinggi, West Sumatra, Indonesia. Its activity is characterized by small vulcanian explosions with occasional VEI 2 producing tephra and pyroclastic flows. Due to its activity, it is being monitored by Centre for Volcanology and Geological Hazard Mitigation (CVGHM). Four seismic stations consists of 2 broadband and 2 short period instruments have been established since 2009. In collaboration with CVGHM, Earth Observatory of Singapore added 5 seismic stations around the volcano in 2014, initially with short period instruments but later upgraded to broadbands. We added one tilt station at the summit of Marapi. These seismic and tilt stations are telemetered by 5.8GHz radio to Marapi Observatory Post where data are archived and displayed for Marapi observers for their daily volcanic activity monitoring work. We also archive the data in the EOS and CVGHM main offices. Here we are presenting examples of seismic and deformation data from Marapi prior, during, and after the vulcanian explosion. Our study attempt to understand the state of the volcano based on monitoring data and in order to enable us to better estimate the hazards associated with the future eruptions of this or similar volcano.

Catalog of earthquake hypocenters at Alaskan volcanoes: January 1, 1994 through December 31, 1999

USGS Publications Warehouse

Jolly, Arthur D.; Stihler, Scott D.; Power, John A.; Lahr, John C.; Paskievitch, John; Tytgat, Guy; Estes, Steve; Lockhart, Andrew B.; Moran, Seth C.; McNutt, Stephen R.; Hammond, William R.

2001-01-01

The Alaska Volcano Observatory (AVO), a cooperative program of the U.S. Geological Survey, the Geophysical Institute of the University of Alaska - Fairbanks, and the Alaska Division of Geological and Geophysical Surveys, has maintained a seismic monitoring program at potentially active volcanoes in Alaska since 1988 (Power and others, 1993; Jolly and others, 1996). The primary objectives of this program are the seismic surveillance of active, potentially hazardous, Alaskan volcanoes and the investigation of seismic processes associated with active volcanism.Between 1994 and 1999, the AVO seismic monitoring program underwent significant changes with networks added at new volcanoes during each summer from 1995 through 1999. The existing network at Katmai –Valley of Ten Thousand Smokes (VTTS) was repaired in 1995, and new networks were installed at Makushin (1996), Akutan (1996), Pavlof (1996), Katmai - south (1996), Aniakchak (1997), Shishaldin (1997), Katmai - north (1998), Westdahl, (1998), Great Sitkin (1999) and Kanaga (1999). These networks added to AVO's existing seismograph networks in the Cook Inlet area and increased the number of AVO seismograph stations from 46 sites and 57 components in 1994 to 121 sites and 155 components in 1999. The 1995–1999 seismic network expansion increased the number of volcanoes monitored in real-time from 4 to 22, including Mount Spurr, Redoubt Volcano, Iliamna Volcano, Augustine Volcano, Mount Snowy, Mount Griggs, Mount Katmai, Novarupta, Trident Volcano, Mount Mageik, Mount Martin, Aniakchak Crater, Pavlof Volcano, Mount Dutton, Isanotski volcano, Shisaldin Volcano, Fisher Caldera, Westdahl volcano, Akutan volcano, Makushin Volcano, Great Sitkin volcano, and Kanaga Volcano (see Figures 1-15). The network expansion also increased the number of earthquakes located from about 600 per year in1994 and 1995 to about 3000 per year between 1997 and 1999.Highlights of the catalog period include: 1) a large volcanogenic seismic swarm at Akutan volcano in March and April 1996 (Lu and others, 2000); 2) an eruption at Pavlof Volcano in fall 1996 (Garces and others, 2000; McNutt and others, 2000); 3) an earthquake swarm at Iliamna volcano between September and December 1996; 4) an earthquake swarm at Mount Mageik in October 1996 (Jolly and McNutt, 1999); 5) an earthquake swarm located at shallow depth near Strandline Lake; 6) a strong swarm of earthquakes near Becharof Lake; 7) precursory seismicity and an eruption at Shishaldin Volcano in April 1999 that included a 5.2 ML earthquake and aftershock sequence (Moran and others, in press; Thompson and others, in press). The 1996 calendar year is also notable as the seismicity rate was very high, especially in the fall when 3 separate areas (Strandline Lake, Iliamna Volcano, and several of the Katmai volcanoes) experienced high rates of located earthquakes.This catalog covers the period from January 1, 1994, through December 31,1999, and includes: 1) earthquake origin times, hypocenters, and magnitudes with summary statistics describing the earthquake location quality; 2) a description of instruments deployed in the field and their locations and magnifications; 3) a description of earthquake detection, recording, analysis, and data archival; 4) velocity models used for earthquake locations; 5) phase arrival times recorded at individual stations; and 6) a summary of daily station usage from throughout the report period. We have made calculated hypocenters, station locations, system magnifications, velocity models, and phase arrival information available for download via computer network as a compressed Unix tar file.

Assessing Magmatic Processes and Hazards at two Basaltic Monogenetic Centers: Volcan Jorullo, Mexico, and Blue Lake Maar, Oregon

NASA Astrophysics Data System (ADS)

Johnson, E. R.; Cashman, K.; Wallace, P.; Delgado Granados, H.

2007-05-01

Although monogenetic basaltic volcanoes exhibit a wide variety of eruption styles, the origin of this diversity is poorly understood and often ignored when assessing volcanic hazards. To better understand magmatic processes and hazards associated with these eruptions, we have studied two monogenetic centers with differing behavior: Volcan Jorullo, a cinder cone in Mexico, and Blue Lake, a maar in the Oregon High Cascades. Although compositionally similar (medium-K basalt to basaltic andesite), their eruptive styles and products are quite different. Jorullo had violent strombolian eruptions that deposited alternating beds of ash and tephra, as well as lava flows. In contrast, Blue Lake exhibited initial phreatomagmatism that formed a 100m deep crater and produced surge deposits. This activity was followed by magmatic eruptions that produced deposits of tephra and bombs, but no lava flows. The diversity in eruptive style at these two centers reflects different magma ascent and crystallization processes, deduced using olivine-hosted melt inclusions. Jorullo melt inclusions trap variably degassed melts (0.5-5 wt% H2O; 0-1000 ppm CO2), with associated crystallization pressures that decrease from early (<4 kbars) to late (<100 bars) in the eruption. These data support the formation of a shallow storage region beneath the volcano that facilitated both crystallization and magma degassing, which is consistent with effusion of degassed lavas from the base of the cone throughout the eruption. In contrast, Blue Lake inclusions trap melts with a restricted range of volatiles (2.6-4 wt% H2O; 677-870 ppm CO2) corresponding to crystallization pressures of 2.2-3.2 kbars. This suggests that the magma feeding Blue Lake stalled in the upper crust and crystallized before ascending rapidly to the surface, without further crystallization of olivine or shallow storage. This is consistent with both the observed unstratified tephra deposits (indicating single rather than pulsatory eruptions) and the absence of lava flows. Our data suggest that in spite of similar compositions and volatile contents, these two volcanoes produced distinctive eruption styles. Although external water clearly played an important role in the eruption at Blue Lake, both volcanoes had explosive, magmatic volatile-driven eruptions. These eruptions clearly show that monogenetic centers are capable of a wide variety of eruptive styles and hazards, which may depend in large part on processes of magma ascent, degassing, and crystallization.

Volcanology and eruptive styles of Barren Island: an active mafic stratovolcano in the Andaman Sea, NE Indian Ocean

NASA Astrophysics Data System (ADS)

Sheth, Hetu C.; Ray, Jyotiranjan S.; Bhutani, Rajneesh; Kumar, Alok; Smitha, R. S.

2009-11-01

Barren Island (India) is a relatively little studied, little known active volcano in the Andaman Sea, and the northernmost active volcano of the great Indonesian arc. The volcano is built of prehistoric (possibly late Pleistocene) lava flows (dominantly basalt and basaltic andesite, with minor andesite) intercalated with volcaniclastic deposits (tuff breccias, and ash beds deposited by pyroclastic falls and surges), which are exposed along a roughly circular caldera wall. There are indications of a complete phreatomagmatic tephra ring around the exposed base of the volcano. A polygenetic cinder cone has existed at the centre of the caldera and produced basalt-basaltic andesite aa and blocky aa lava flows, as well as tephra, during historic eruptions (1787-1832) and three recent eruptions (1991, 1994-95, 2005-06). The recent aa flows include a toothpaste aa flow, with tilted and overturned crustal slabs carried atop an aa core, as well as locally developed tumuli-like elliptical uplifts having corrugated crusts. Based on various evidence we infer that it belongs to either the 1991 or the 1994-95 eruptions. The volcano has recently (2008) begun yet another eruption, so far only of tephra. We make significantly different interpretations of several features of the volcano than previous workers. This study of the volcanology and eruptive styles of the Barren Island volcano lays the ground for detailed geochemical-isotopic and petrogenetic work, and provides clues to what the volcano can be expected to do in the future.

Cyclic Activity of Mud Volcanoes: Evidences from Trinidad (SE Caribbean)

NASA Astrophysics Data System (ADS)

Deville, E.

2007-12-01

Fluid and solid transfer in mud volcanoes show different phases of activity, including catastrophic events followed by periods of relative quiescence characterized by moderate activity. This can be notably shown by historical data onshore Trinidad. Several authors have evoked a possible link between the frequencies of eruption of some mud volcanoes and seismic activity, but in Trinidad there is no direct correlation between mud eruptions and seisms. It appears that each eruptive mud volcano has its own period of catastrophic activity, and this period is highly variable from one volcano to another. The frequency of activity of mud volcanoes seems essentially controlled by local pressure regime within the sedimentary pile. At the most, a seism can, in some cases, activate an eruption close to its term. The dynamics of expulsion of the mud volcanoes during the quiescence phases has been studied notably from temperature measurements within the mud conduits. The mud temperature is concurrently controlled by, either, the gas flux (endothermic gas depressurizing induces a cooling effect), or by the mud flux (mud is a vector for convective heat transfer). Complex temperature distribution was observed in large conduits and pools. Indeed, especially in the bigger pools, the temperature distribution characterizes convective cells with an upward displacement of mud above the deep outlet, and ring-shaped rolls associated with the burial of the mud on the flanks of the pools. In simple, tube-like shaped, narrow conduits, the temperature is more regular, but we observed different types of profiles, with either downward increasing or decreasing temperatures. If the upward flow of mud would be regular, we should expect increasing temperatures and progressively decreasing gradient with depth within the conduits. However, the variable measured profiles from one place to another, as well as time-variable measured temperatures within the conduits and especially, at the base of the conduits, shows that the fluid flow expelled by the studied mud volcanoes is not constant but highly variable through short time-periods. We notably observed very short time-period cyclic variations with a frequency of about 10 minutes. These high frequencies temperature changes could be related to the dynamics of two-phase flows (gas and mud) through the mud volcano conduits. We also observed locally a significant daily changes of the temperature of the expelled mud which shows also that the mud flux is changing very rapidly from one day to another.

One hundred years of volcano monitoring in Hawaii

USGS Publications Warehouse

Kauahikaua, Jim; Poland, Mike

2012-01-01

In 2012 the Hawaiian Volcano Observatory (HVO), the oldest of five volcano observatories in the United States, is commemorating the 100th anniversary of its founding. HVO's location, on the rim of Kilauea volcano (Figure 1)—one of the most active volcanoes on Earth—has provided an unprecedented opportunity over the past century to study processes associated with active volcanism and develop methods for hazards assessment and mitigation. The scientifically and societally important results that have come from 100 years of HVO's existence are the realization of one man's vision of the best way to protect humanity from natural disasters. That vision was a response to an unusually destructive decade that began the twentieth century, a decade that saw almost 200,000 people killed by the effects of earthquakes and volcanic eruptions.

One hundred years of volcano monitoring in Hawaii

USGS Publications Warehouse

Kauahikaua, J.; Poland, M.

2012-01-01

In 2012 the Hawaiian Volcano Observatory (HVO), the oldest of five volcano observatories in the United States, is commemorating the 100th anniversary of its founding. HVO's location, on the rim of Klauea volcano (Figure 1)one of the most active volcanoes on Earthhas provided an unprecedented opportunity over the past century to study processes associated with active volcanism and develop methods for hazards assessment and mitigation. The scientifically and societally important results that have come from 100 years of HVO's existence are the realization of one man's vision of the best way to protect humanity from natural disasters. That vision was a response to an unusually destructive decade that began the twentieth century, a decade that saw almost 200,000 people killed by the effects of earthquakes and volcanic eruptions.

Analysis of Distribution of Volcanoes around the Korean Peninsula and the Potential Effects on Korea

NASA Astrophysics Data System (ADS)

Choi, Eun-kyeong; Kim, Sung-wook

2017-04-01

Since the scale and disaster characteristics of volcanic eruptions are determined by their geological features, it is important not only to grasp the current states of the volcanoes in neighboring countries around the Korean Peninsula, but also to analyze the tectonic settings, tectonic regions, geological features, volcanic types, and eruption histories of these volcanoes. Volcanic data were based on the volcano information registered with the Global Volcanism Program at the Smithsonian Institute. We created a database of 289 volcanoes around Korea, Japan, China, Taiwan, and the Kamchatka area in Russia, and then identified a high-risk group of 29 volcanoes that are highly likely to affect the region, based on conditions such as volcanic activity, types of rock at risk of eruption, distance from Seoul, and volcanoes having Plinian eruption history with volcanic explosivity index (VEI) of 4 or more. We selected 29 hazardous volcanoes, including Baekdusan, Ulleungdo, and 27 Japanese volcanoes that can cause widespread ashfall on the Korean peninsula by potentially explosive eruptions. In addition, we identified ten volcanoes that should be given the highest priority, through an analysis of data available in literature, such as volcanic ash dispersion results from previous Japanese eruptions, the definition of a large-scale volcano used by Japan's Cabinet Office, and examination of cumulative magma layer volumes from Japan's quaternary volcanoes. We expect that predicting the extent of the spread of ash caused by this hazardous activity and analyzing its impact on the Korean peninsula will be help to predict volcanic ash damage as well as provide direction for hazard mitigation research. Acknowledgements This research was supported by a grant [MPSS-NH-2015-81] through the Disaster and Safety Management Institute funded by Ministry of Public Safety and Security of Korean government.

Time-variation of hydrothermal discharge at selected sites in the Western United States: Implications for monitoring

USGS Publications Warehouse

Ingebritsen, S.E.; Galloway, D.L.; Colvard, E.M.; Sorey, M.L.; Mariner, R.H.

2001-01-01

We compiled time series of hydrothermal discharge consisting of 3593 chloride- or heat-flux measurements from 24 sites in the Yellowstone region, the northern Oregon Cascades, Lassen Volcanic National Park and vicinity, and Long Valley, California. At all of these sites the hydrothermal phenomena are believed to be as yet unaffected by human activity, though much of the data collection was driven by mandates to collect environmental-baseline data in acticipation of geothermal development. The time series average 19 years in length and some of the Yellowstone sites have been monitored intermittently for over 30 years. Many sites show strong seasonality but few show clear long-term trends, and at most sites statistically significant decadal-scale trends are absent. Thus, the data provide robust estimates of advective heat flow ranging from ~130 MW in the north-central Oregon Cascades to ~6100 MW in the Yellowstone region, and also document Yellowstone hydrothermal chloride and arsenic fluxes of 1740 and 15-20 g/s, respectively. The discharge time series show little sensitivity to regional tectonic events such as earthquakes or inflation/deflation cycles. Most long-term monitoring to date has focused on high-chloride springs and low-temperature fumaroles. The relative stability of these features suggests that discharge measurements done as part of volcano-monitoring programs should focus instead on high-temperature fumaroles, which may be more immediately linked to the magmatic heat source. ?? 2001 Elsevier Science B.V. All rights reserved.

Estimating eruption temperature from thermal emission spectra of lava fountain activity in the Erta'Ale (Ethiopia) volcano lava lake: Implications for observing Io's volcanoes

USGS Publications Warehouse

Davies, Ashley G.; Keszthelyi, Laszlo P.; McEwen, Alfred S.

2011-01-01

We have analysed high-spatial-resolution and high-temporal-resolution temperature measurements of the active lava lake at Erta'Ale volcano, Ethiopia, to derive requirements for measuring eruption temperatures at Io's volcanoes. Lava lakes are particularly attractive targets because they are persistent in activity and large, often with ongoing lava fountain activity that exposes lava at near-eruption temperature. Using infrared thermography, we find that extracting useful temperature estimates from remote-sensing data requires (a) high spatial resolution to isolate lava fountains from adjacent cooler lava and (b) rapid acquisition of multi-color data. Because existing spacecraft data of Io's volcanoes do not meet these criteria, it is particularly important to design future instruments so that they will be able to collect such data. Near-simultaneous data at more than two relatively short wavelengths (shorter than 1 μm) are needed to constrain eruption temperatures. Resolving parts of the lava lake or fountains that are near the eruption temperature is also essential, and we provide a rough estimate of the required image scale.

Linked halokinesis and mud volcanism at the Mercator mud volcano, Gulf of Cadiz

NASA Astrophysics Data System (ADS)

Perez-Garcia, Carolina; Berndt, Christian; Klaeschen, Dirk; Mienert, Jürgen; Haffert, Laura; Depreiter, Davy; Haeckel, Matthias

2011-05-01

Mud volcanoes are seafloor expressions of focused fluid flow that are common in compressional tectonic settings. New high-resolution 3-D seismic data from the Mercator mud volcano (MMV) and an adjacent buried mud volcano (BMV) image the internal structure of the top 800 m of sediment at both mud volcanoes, revealing that both are linked and have been active episodically. The total volumes of extruded mud range between 0.15 and 0.35 km3 and 0.02-0.05 km3 for the MMV and the BMV, respectively. The pore water composition of surface sediment samples suggests that halokinesis has played an important role in the evolution of the mud volcanoes. We propose that erosion of the top of the Vernadsky Ridge that underlies the mud volcanoes activated salt movement, triggering deep migration of fluids, dissolution of salt, and sediment liquefaction and mobilization since the end of the Pliocene. Since beginning of mud volcanism in this area, the mud volcanoes erupted four times while there was only one reactivation of salt tectonics. This implies that there are other mechanisms that trigger mud eruptions. The stratigraphic relationship of mudflows from the MMV and BMV indicates that the BMV was triggered by the MMV eruptions. This may either be caused by loading-induced hydrofracturing within the BMV or due to a common feeder system for both mud volcanoes. This study shows that the mud volcanoes in the El Arraiche mud volcano field are long-lived features that erupt with intervals of several tens of thousands of years.

Engaging with the Public on Volcanic Risk through Hands-on Interaction with the London Volcano.

NASA Astrophysics Data System (ADS)

Rodgers, M.; Pyle, D. M.; Barclay, J.; Mather, T. A.; Hicks, A.; Ratner, J.; Leonard, H.; Woods, C.

2015-12-01

London Volcano is a major public engagement and outreach effort that emerged from a large-scale interdisciplinary research project on Strengthening Resilience in Volcanic Areas (STREVA). The activity was created for a 5-day public exhibition in London, in 2014, and brought together 3 elements to illustrate the timeline of a volcanic crisis: a 5m x 3m scale model of Soufrière St Vincent, an interactive 'monitoring station' to explore technology used in monitoring and an engaging 'bin bang' sequence to simulate a volcanic explosion. Having a large hands-on volcano as a centrepiece to the exhibit enabled interaction with primary-age school children through the use of creativity and imagination. They looked at seismic traces of 'bin bang' explosions; measured dispersal of projectile ducks; and decided where to place a model house on the island, on which the model volcano sat. Over the 5-days we evolved the activity of the volcano to re-create the 1902 eruption. During the first 3 days, 94 houses were placed around the volcano, but after the cataclysmic eruption mid-week, 12 of these houses were destroyed by simulated pyroclastic flows and lahars down the flanks of the volcano model. Light and sound were key parts of the London Volcano simulation. A sound track was created to mimic the sounds reported by eyewitnesses. Between eruptions, the volcano would intermittently rumble, adding excitement and unpredictability to the eruptions. Explosions were simulated with compressed-CO2 jets, and a G-flame; but these events were rare. Creative arts are an effective mechanism for transfer of knowledge from communities living with volcanic activity, so artwork from school children living near Tungurahua, Ecuador and poems from school children on Montserrat were on display. The London Volcano was a unique opportunity to engage with over 2,000 people on volcanic risk and what it means to live near a volcano. Encouraging school children to be creative and to use their imagination allowed the volcano to come alive in ways that would have otherwise been impossible.

Earth Observations

NASA Image and Video Library

2010-07-15

ISS024-E-008396 (15 July 2010) --- Sabancaya volcano in Peru is featured in this image photographed by an Expedition 24 crew member on the International Space Station. The 5,967-meter-high Sabancaya stratovolcano (or Nevado Sabancaya) is located in southern Peru approximately 70 kilometers to the northwest of the city of Arequipa. The name Sabancaya means ?tongue of fire? in the Quechua Indian language. Sabancaya is part of a volcanic complex that includes two other nearby (and older) volcanoes, neither of which has been active historically; in this detailed photograph, Nevado Ampato is visible to the south (top center) and the lower flanks of Nevado Hualca Hualca are visible to the north (bottom right). The snowy peaks of the three volcanoes provide a stark contrast to the surrounding desert of the Puna Plateau. Sabancaya?s first historical record of an eruption dates to 1750. The most recent eruptive activity at the volcano occurred in July 2003 and deposited ash on the volcano?s summit and northeastern flank. Volcanism at Sabancaya is fueled by magma generated at the subduction zone between the Nazca and South American tectonic plates. Magma can erupt to the surface and form lava flows through the volcano?s summit (frequently forming a crater) but can also erupt from lava domes and flank vents along the volcano?s sides. Lava has issued from all of these points at Sabancaya, forming numerous gray to dark brown lobate flows that extend in all directions except southwards (center).

Mt. St. Helens Memories.

ERIC Educational Resources Information Center

Sharp, Len

1992-01-01

Provides a personal account of one science teacher's participation in a teacher workshop in which teachers learned about volcanic development, types of eruption, geomorphology, plate tectonics, volcano monitoring, and hazards created by volcanoes by examining Mt. St. Helens. Provides a graphic identifying volcanoes active since 1975. (MDH)

Geoflicks Reviewed--Films about Hawaiian Volcanoes.

ERIC Educational Resources Information Center

Bykerk-Kauffman, Ann

1994-01-01

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

Aniakchak Crater, Alaska Peninsula

USGS Publications Warehouse

Smith, Walter R.

1925-01-01

The discovery of a gigantic crater northwest of Aniakchak Bay (see fig. 11) closes what had been thought to be a wide gap in the extensive series of volcanoes occurring at irregular intervals for nearly 600 miles along the axial line of the Alaska Peninsula and the Aleutian Islands. In this belt there are more active and recently active volcanoes than in all the rest of North America. Exclusive of those on the west side of Cook Inlet, which, however, belong to the same group, this belt contains at least 42 active or well-preserved volcanoes and about half as many mountains suspected or reported to be volcanoes. The locations of some of these mountains and the hot springs on the Alaska Peninsula and the Aleutian Islands are shown on a map prepared by G. A. Waring. Attention has been called to these volcanoes for nearly two centuries, but a record of their activity since the discovery of Alaska is far from being complete, and an adequate description of them as a group has never been written. Owing to their recent activity or unusual scenic beauty, some of the best known of the group are Mounts Katmai, Bogoslof, and Shishaldin, but there are many other beautiful and interesting cones and craters.

Catalog of earthquake hypocenters at Alaskan volcanoes: January 1 through December 31, 2004

USGS Publications Warehouse

Dixon, James P.; Stihler, Scott D.; Power, John A.; Tytgat, Guy; Estes, Steve; Prejean, Stephanie; Sanchez, John J.; Sanches, Rebecca; McNutt, Stephen R.; Paskievitch, John

2005-01-01

The Alaska Volcano Observatory (AVO), a cooperative program of the U.S. Geological Survey, the Geophysical Institute of the University of Alaska Fairbanks, and the Alaska Division of Geological and Geophysical Surveys, has maintained seismic monitoring networks at historically active volcanoes in Alaska since 1988. The primary objectives of the seismic program are the real-time seismic monitoring of active, potentially hazardous, Alaskan volcanoes and the investigation of seismic processes associated with active volcanism. This catalog presents the calculated earthquake hypocenter and phase arrival data, and changes in the seismic monitoring program for the period January 1 through December 31, 2004.These include Mount Wrangell, Mount Spurr, Redoubt Volcano, Iliamna Volcano, Augustine Volcano, Katmai volcanic cluster (Snowy Mountain, Mount Griggs, Mount Katmai, Novarupta, Trident Volcano, Mount Mageik, Mount Martin), Mount Peulik, Aniakchak Crater, Mount Veniaminof, Pavlof Volcano, Mount Dutton, Isanotski Peaks, Shishaldin Volcano, Fisher Caldera, Westdahl Peak, Akutan Peak, Makushin Volcano, Okmok Caldera, Great Sitkin Volcano, Kanaga Volcano, Tanaga Volcano, and Mount Gareloi. Over the past year, formal monitoring of Okmok, Tanaga and Gareloi were announced following an extended period of monitoring to determine the background seismicity at each volcanic center. The seismicity at Mount Peulik was still being studied at the end of 2004 and has yet to be added to the list of monitored volcanoes in the AVO weekly update. AVO located 6928 earthquakes in 2004.Monitoring highlights in 2004 include: (1) an earthquake swarm at Westdahl Peak in January; (2) an increase in seismicity at Mount Spurr starting in February continuing through the end of the year into 2005; (4) low-level tremor, and low-frequency events related to intermittent ash and steam emissions at Mount Veniaminof between April and October; (4) low-level tremor at Shishaldin Volcano between April and October; (5) an earthquake swarm at Akutan in July; and (6) low-level tremor at Okmok Caldera throughout the year (Table 2). Instrumentation and data acquisition highlights in 2004 were the installation of subnetworks on Mount Peulik and Korovin Volcano and the installation of broadband stations to augment the Katmai and Spurr subnetworks.This catalog includes: (1) a description of instruments deployed in the field and their locations; (2) a description of earthquake detection, recording, analysis, and data archival systems; (3) a description of velocity models used for earthquake locations; (4) a summary of earthquakes located in 2004; and (5) an accompanying UNIX tar-file with a summary of earthquake origin times, hypocenters, magnitudes, phase arrival times, and location quality statistics; daily station usage statistics; and all HYPOELLIPSE files used to determine the earthquake locations in 2004.

Communicating Uncertainty to the Public During Volcanic Unrest and Eruption -A Case Study From the 2004-2005 Eruption of Mount St. Helens, USA

NASA Astrophysics Data System (ADS)

Gardner, C. A.; Pallister, J. S.

2005-12-01

The earthquake swarm beneath Mount St. Helens that began on 23 September 2004 did not initially appear different from previous swarms (none of which culminated in an eruption) that had occurred beneath the volcano since the end of the 1980-1986 eruptions. Three days into the swarm, however, a burst of larger-magnitude earthquakes indicated that this swarm was indeed different and prompted the U.S. Geological Survey's Cascades Volcano Observatory (CVO) to issue a change in alert level, the first time such a change had been issued in the Cascades in over 18 years. From then on, the unrest accelerated quickly as did the need to communicate the developing conditions to the public and public officials, often in the spotlight of intense media attention. Within three weeks of the onset of unrest, magma reached the surface. Since mid-October 2004, lava has been extruding through a glacier within the crater of Mount St. Helens, forming a 60 Mm3 dome by August 2005. The rapid onset of the eruption required a rapid ramping up of communication within and among the scientific, emergency-response and land-management communities, as well as the reestablishment of protocols that had not been rigorously tested for 18 years. Early on, daily meetings of scientists from CVO and the University of Washington's Pacific Northwest Seismograph Network were established to discuss incoming monitoring data and to develop a consensus on the likely course of activity, hazard potential and the uncertainty inherent in these forecasts. Subgroups developed scenario maps to describe the range of activity likely under different eruptive behaviors and sizes, and assessed short- and long-term probabilities of eruption, explosivity and hazardous events by employing a probability-tree methodology. Resultant consensual information has been communicated to a variety of groups using established alert levels for ground-based and aviation communities, daily updates and media briefings, postings on the worldwide web, teleconferences, and meetings with land and emergency managers. Initial concerns revolved around the questions of if and when an eruption would occur, whether it would be explosive, and how large-all questions without definitive answers. As the eruption progresses, concerns have transformed to whether the eruptive behavior will change and how long the eruption will last-also questions lacking definitive answers. We have found it important in communicating our uncertainty to the public to articulate how we came to our conclusions and why our answers cannot be more definitive. We have also found that framing volcanic uncertainty in terms of more common analogies (e.g. knowing that conditions are right for development of a tornado, but not being able to predict exactly when a funnel cloud will form, precisely where it will touch down, or how severe the damage will be) appears to help the public and public officials understand volcanic uncertainty better. As the eruption continues and people become more accustomed to the activity, we find an increasingly more knowledgeable public who can better understand and deal with uncertainty. Also, it is clear that establishing interagency relationships by developing volcano response plans before a crisis greatly facilitates a successful response. A critical component of this planning is discussing uncertainties inherent during volcanic crises such that when unrest begins, the concept of, and reasons behind uncertainty are already well understood.

Geologic map of the Sauk River 30- by 60-minute quadrangle, Washington

USGS Publications Warehouse

Tabor, R.W.; Booth, D.B.; Vance, J.A.; Ford, A.B.

2002-01-01

Summary -- The north-south-trending regionally significant Straight Creek Fault roughly bisects the Sauk River quadrangle and defines the fundamental geologic framework of it. Within the quadrangle, the Fault mostly separates low-grade metamorphic rocks on the west from medium- to high-grade metamorphic rocks of the Cascade metamorphic core. On the west, the Helena-Haystack melange and roughly coincident Darrington-Devils Mountain Fault Zone separate the western and eastern melange belts to the southwest from the Easton Metamorphic Suite, the Bell Pass melange, and rocks of the Chilliwack Group, to the northeast. The tectonic melanges have mostly Mesozoic marine components whereas the Chilliwack is mostly composed of Late Paleozoic arc rocks. Unconformably overlying the melanges and associated rocks are Eocene volcanic and sedimentary rocks, mostly infaulted along the Darrington-Devils Mountain Fault Zone. These younger rocks and a few small Eocene granitic plutons represent an extensional tectonic episode. East of the Straight Creek Fault, medium to high-grade regional metamorphic rocks of the Nason, Chelan Mountains, and Swakane terranes have been intruded by deep seated, Late Cretaceous granodioritic to tonalitic plutons, mostly now orthogneisses. Unmetamorphosed mostly tonalitic intrusions on both sides of the Straight Creek fault range from 35 to 4 million years old and represent the roots of volcanoes of the Cascade Magmatic Arc. Arc volcanic rocks are sparsely preserved east of the Straight Creek fault, but dormant Glacier Peak volcano on the eastern margin of the quadrangle is the youngest member of the Arc. Deposits of the Canadian Ice Sheet are well represented on the west side of the quadrangle, whereas alpine glacial deposits are common to the east. Roughly 5000 years ago lahars from Glacier Peak flowed westward filling major valleys across the quadrangle.

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

NASA Astrophysics Data System (ADS)

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.

Preliminary volcano-hazard assessment for Great Sitkin Volcano, Alaska

USGS Publications Warehouse

Waythomas, Christopher F.; Miller, Thomas P.; Nye, Christopher J.

2003-01-01

Great Sitkin Volcano is a composite andesitic stratovolcano on Great Sitkin Island (51°05’ N latitude, 176°25’ W longitude), a small (14 x 16 km), circular volcanic island in the western Aleutian Islands of Alaska. Great Sitkin Island is located about 35 kilometers northeast of the community of Adak on Adak Island and 130 kilometers west of the community of Atka on Atka Island. Great Sitkin Volcano is an active volcano and has erupted at least eight times in the past 250 years (Miller and others, 1998). The most recent eruption in 1974 caused minor ash fall on the flanks of the volcano and resulted in the emplacement of a lava dome in the summit crater. The summit of the composite cone of Great Sitkin Volcano is 1,740 meters above sea level. The active crater is somewhat lower than the summit, and the highest point along its rim is about 1,460 meters above sea level. The crater is about 1,000 meters in diameter and is almost entirely filled by a lava dome emplaced in 1974. An area of active fumaroles, hot springs, and bubbling hot mud is present on the south flank of the volcano at the head of Big Fox Creek (see the map), and smaller ephemeral fumaroles and steam vents are present in the crater and around the crater rim. The flanking slopes of the volcano are gradual to steep and consist of variously weathered and vegetated blocky lava flows that formed during Pleistocene and Holocene eruptions. The modern edifice occupies a caldera structure that truncates an older sequence of lava flows and minor pyroclastic rocks on the east side of the volcano. The eastern sector of the volcano includes the remains of an ancestral volcano that was partially destroyed by a northwest-directed flank collapse. In winter, Great Sitkin Volcano is typically completely snow covered. Should explosive pyroclastic eruptions occur at this time, the snow would be a source of water for volcanic mudflows or lahars. In summer, much of the snowpack melts, leaving only a patchy distribution of snow on the volcano. Glacier ice is no longer present on the volcano or on other parts of Great Sitkin Island as previously reported by Simons and Mathewson (1955). Great Sitkin Island is presently uninhabited and is part of the Alaska Maritime National Wildlife Refuge, managed by the U.S. Fish and Wildlife Service.

Earth Observations taken by Expedition 38 crewmember

NASA Image and Video Library

2013-11-15

ISS038-E-003612 (15 Nov. 2013) --- Islands of the Four Mountains are featured in this image photographed by an Expedition 38 crew member on the International Space Station. Morning sunlight illuminates the southeast-facing slopes of the islands in the photograph. The islands, part of the Aleutian Island chain, are actually the upper slopes of volcanoes rising from the sea floor; Carlisle, Cleveland, Herbert, and Tana. Carlisle and Herbert volcanoes are distinct cones and form separate islands. Cleveland volcano and the Tana volcanic complex form the eastern and western ends respectively of Chuginadak Island; a cloud bank obscures the connecting land mass in this image. Cleveland volcano (peak elevation 1,730 meters above sea level) is one of the most active in the Aleutian chain, with its most recent activity--eruptions and lava flow emplacement--taking place in May of 2013. The northernmost of the islands, Carlisle volcano's (peak elevation 1,620 meters above sea level) last confirmed eruption occurred in 1828, with unconfirmed reports of activity in 1987. Herbert volcano (peak elevation 1,280 meters above sea level) to the southwest displays a classic cone structure breached by a two-kilometer wide summit caldera (upper right), but there are no historical records of volcanic activity. The easternmost peak, Tana (1,170 meters above sea level) is a volcanic complex comprised of two east-west trending volcanoes and associated younger cinder cones; like Herbert volcano, there is no historical record of activity at Tana. A layer of low clouds and/or fog obscures much of the lower elevations of the islands and the sea surface, but the clouds also indicate the general airflow pattern around and through the islands. Directly to the south-southeast of Cleveland volcano a Von Karman vortex "street" is visible. Shadows cast by the morning sun extend from the peaks towards the northwest. The peaks of all of the Four Islands have snow cover; this is distinct from the clouds due to both higher brightness (white versus gray) and specific location on the landscape.

Orographic Flow over an Active Volcano

NASA Astrophysics Data System (ADS)

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

2014-05-01

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

Implications for future activity of Grímsvötn volcano, Iceland, from compositional time series of historical tephra

NASA Astrophysics Data System (ADS)

Carpentier, Marion; Sigmarsson, Olgeir; Larsen, Gudrun

2014-05-01

The nature of future eruptions of active volcanoes is hard to predict. Improved understanding of the past volcanic activity is probably the best way to infer future eruptive scenarios. The most active volcano in Iceland, Grímsvötn, last erupted in 2011 with consequences for habitants living close to the volcano and aviation in the North-Atlantic. In an effort to better understand the magmatic system of the volcano, we have investigated the compositions of 23 selected tephra layers representing the last 8 centuries of volcanic activity at Grímsvötn. The tephra was collected in the ablation area of outlet glaciers from Vatnajökull ice cap. The ice-conserved tephra are less prone to alteration than those exposed in soil sections. Major element analyses are indistinguishable and of quartz-normative tholeiite composition, and Sr and Nd isotope ratios are constant. In contrast, both trace element concentrations (Th range from 0.875 ppm to 1.37 ppm and Ni from 28.5 ppm to 56.6 ppm) in the basalts and Pb isotopes show small but significant variations. The high-precision analyses of Pb isotope ratios allow the identification of tephra samples (3 in total) with more radiogenic ratios than the bulk of the samples. The tephra of constant isotope ratios show linear increase in incompatible element concentrations with time. The rate of increasing concentrations permits exploring possible future scenarios assuming that the magmatic system beneath the volcano follows the established historical evolution. Assuming similar future behaviour of the magma system beneath Grímsvötn volcano, the linear increase in e.g. Th concentration suggests that the volcano is likely to principally produce basalts for the next 500-1000 years. Evolution of water concentration will most likely follow those of incompatible elements with consequent increases in explosiveness of future Grímsvötn eruptions.

Volcanic versus anthropogenic carbon dioxide

USGS Publications Warehouse

Gerlach, T.

2011-01-01

Which emits more carbon dioxide (CO2): Earth's volcanoes or human activities? Research findings indicate unequivocally that the answer to this frequently asked question is human activities. However, most people, including some Earth scientists working in fields outside volcanology, are surprised by this answer. The climate change debate has revived and reinforced the belief, widespread among climate skeptics, that volcanoes emit more CO2 than human activities [Gerlach, 2010; Plimer, 2009]. In fact, present-day volcanoes emit relatively modest amounts of CO2, about as much annually as states like Florida, Michigan, and Ohio.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Benkovitz, C.M.

Sulfur emissions from volcanoes are located in areas of volcanic activity, are extremely variable in time, and can be released anywhere from ground level to the stratosphere. Previous estimates of global sulfur emissions from all sources by various authors have included estimates for emissions from volcanic activity. In general, these global estimates of sulfur emissions from volcanoes are given as global totals for an ``average`` year. A project has been initiated at Brookhaven National Laboratory to compile inventories of sulfur emissions from volcanoes. In order to complement the GEIA inventories of anthropogenic sulfur emissions, which represent conditions circa specific years,more » sulfur emissions from volcanoes are being estimated for the years 1985 and 1990.« less

A model of diffuse degassing at three subduction-related volcanoes

NASA Astrophysics Data System (ADS)

Williams-Jones, Glyn; Stix, John; Heiligmann, Martin; Charland, Anne; Sherwood Lollar, Barbara; Arner, N.; Garzón, Gustavo V.; Barquero, Jorge; Fernandez, Erik

Radon, CO2 and δ13C in soil gas were measured at three active subduction-related stratovolcanoes (Arenal and Poás, Costa Rica; Galeras, Colombia). In general, Rn, CO2 and δ13C values are higher on the lower flanks of the volcanoes, except near fumaroles in the active craters. The upper flanks of these volcanoes have low Rn concentrations and light δ13C values. These observations suggest that diffuse degassing of magmatic gas on the upper flanks of these volcanoes is negligible and that more magmatic degassing occurs on the lower flanks where major faults and greater fracturing in the older lavas can channel magmatic gases to the surface. These results are in contrast to findings for Mount Etna where a broad halo of magmatic CO2 has been postulated to exist over much of the edifice. Differences in radon levels among the three volcanoes studied here may result from differences in age, the degree of fracturing and faulting, regional structures or the level of hydrothermal activity. Volcanoes, such as those studied here, act as plugs in the continental crust, focusing magmatic degassing towards crater fumaroles, faults and the fractured lower flanks.

International Space Station (ISS)

NASA Image and Video Library

2001-07-22

An Expedition Two crewmember aboard the International Space Station (ISS) captured this overhead look at the smoke and ash regurgitated from the erupting volcano Mt. Etna on the island of Sicily, Italy. At an elevation of 10,990 feet (3,350 m), the summit of the Mt. Etna volcano, one of the most active and most studied volcanoes in the world, has been active for a half-million years and has erupted hundreds of times in recorded history.

Analysis of Active Lava Flows on Kilauea Volcano, Hawaii, Using SIR-C Radar Correlation Measurements

NASA Technical Reports Server (NTRS)

Zebker, H. A.; Rosen, P.; Hensley, S.; Mouginis-Mark, P. J.

1995-01-01

Precise eruption rates of active pahoehoe lava flows on Kilauea volcano, Hawaii, have been determined using spaceborne radar data acquired by the Space Shuttle Imaging Radar-C (SIR-C). Measurement of the rate of lava flow advance, and the determination of the volume of new material erupted in a given period of time, are among the most important observations that can be made when studying a volcano.

Geothermal Energy in the Pacific Region

DTIC Science & Technology

1975-05-01

drilled at Kilauea Volcano , on 0 the Island of Hawaii , by the Colorado Sohool of Mines under a National Science Foundation grant. A second test well has...34•olombia belt of active volcanoes where dacite is commonly reported. The simatic Pacific Basin harbors several areas of active volcanism: Hawaii , Galapagos...reef-capped volcanoes . Numerous articles have been written on many aspects of the geology of Hawaii and notable books include Macdonald and hbbott (1970

Determining Volcanic Deformation at San Miguel Volcano, El Salvador by Integrating Radar Interferometry and Seismic Analyses

NASA Astrophysics Data System (ADS)

Schiek, C. G.; Hurtado, J. M.; Velasco, A. A.; Buckley, S. M.; Escobar, D.

2008-12-01

From the early 1900's to the present day, San Miguel volcano has experienced many small eruptions and several periods of heightened seismic activity, making it one of the most active volcanoes in the El Salvadoran volcanic chain. Prior to 1969, the volcano experienced many explosive eruptions with Volcano Explosivity Indices (VEI) of 2. Since then, eruptions have decreased in intensity to an average VEI of 1. Eruptions mostly consist of phreatic explosions and central vent eruptions. Due to the explosive nature of this volcano, it is important to study the origins of the volcanism and its relationship to surface deformation and earthquake activity. We analyze these interactions by integrating interferometric synthetic aperture radar (InSAR) results with earthquake source location data from a ten-month (March 2007-January 2008) seismic deployment. The InSAR results show a maximum of 7 cm of volcanic inflation from March 2007 to mid-October 2007. During this time, seismic activity increased to a Real-time Seismic-Amplitude Measurement (RSAM) value of >400. Normal RSAM values for this volcano are <50. A period of quiescence began in mid-October 2007, and a maximum of 6 cm of deflation was observed in the interferometry results from 19 October 2007 to 19 January 2008. A clustering of at least 25 earthquakes that occurred between March 2007 and January 2008 suggests a fault zone through the center of the San Miguel volcanic cone. This fault zone is most likely where dyke propagation is occurring. Source mechanisms will be determined for the earthquakes associated with this fault zone, and they will be compared to the InSAR deformation field to determine if the mid-October seismic activity and observed surface deformation are compatible.

Deformation and rupture of the oceanic crust may control growth of Hawaiian volcanoes

USGS Publications Warehouse

Got, J.-L.; Monteiller, V.; Monteux, J.; Hassani, R.; Okubo, P.

2008-01-01

Hawaiian volcanoes are formed by the eruption of large quantities of basaltic magma related to hot-spot activity below the Pacific Plate. Despite the apparent simplicity of the parent process - emission of magma onto the oceanic crust - the resulting edifices display some topographic complexity. Certain features, such as rift zones and large flank slides, are common to all Hawaiian volcanoes, indicating similarities in their genesis; however, the underlying mechanism controlling this process remains unknown. Here we use seismological investigations and finite-element mechanical modelling to show that the load exerted by large Hawaiian volcanoes can be sufficient to rupture the oceanic crust. This intense deformation, combined with the accelerated subsidence of the oceanic crust and the weakness of the volcanic edifice/oceanic crust interface, may control the surface morphology of Hawaiian volcanoes, especially the existence of their giant flank instabilities. Further studies are needed to determine whether such processes occur in other active intraplate volcanoes. ??2008 Nature Publishing Group.

Deformation and rupture of the oceanic crust may control growth of Hawaiian volcanoes.

PubMed

Got, Jean-Luc; Monteiller, Vadim; Monteux, Julien; Hassani, Riad; Okubo, Paul

2008-01-24

Hawaiian volcanoes are formed by the eruption of large quantities of basaltic magma related to hot-spot activity below the Pacific Plate. Despite the apparent simplicity of the parent process--emission of magma onto the oceanic crust--the resulting edifices display some topographic complexity. Certain features, such as rift zones and large flank slides, are common to all Hawaiian volcanoes, indicating similarities in their genesis; however, the underlying mechanism controlling this process remains unknown. Here we use seismological investigations and finite-element mechanical modelling to show that the load exerted by large Hawaiian volcanoes can be sufficient to rupture the oceanic crust. This intense deformation, combined with the accelerated subsidence of the oceanic crust and the weakness of the volcanic edifice/oceanic crust interface, may control the surface morphology of Hawaiian volcanoes, especially the existence of their giant flank instabilities. Further studies are needed to determine whether such processes occur in other active intraplate volcanoes.

Earth Observation taken by the Expedition 33 crew

NASA Image and Video Library

2012-11-03

ISS033-E-018010 (3 Nov. 2012) --- Volcanoes in central Kamchatka are featured in this image photographed by an Expedition 33 crew member on the International Space Station. The snow-covered peaks of several volcanoes of the central Kamchatka Peninsula are visible standing above a fairly uniform cloud deck that obscures the surrounding lowlands. In addition to the rippled cloud patterns caused by interactions of air currents and the volcanoes, a steam and ash plume is visible at center extending north-northeast from the relatively low summit (2,882 meters above sea level) of Bezymianny volcano. Volcanic activity in this part of Russia is relatively frequent, and well monitored by Russia’s Kamchatka Volcanic Eruption Response Team (KVERT). The KVERT website provides updated information about the activity levels on the peninsula, including aviation alerts and webcams. Directly to the north and northeast of Bezymianny, the much larger and taller stratovolcanoes Kamen (4,585 meters above sea level) and Kliuchevskoi (4,835 meters above sea level) are visible. Kliuchevskoi, Kamchatka’s most active volcano, last erupted in 2011 whereas neighboring Kamen has not erupted during the recorded history of the region. An explosive eruption from the summit of the large volcanic massif of Ushkovsky (3,943 meters above sea level; left) northwest of Bezymianny occurred in 1890; this is the most recent activity at this volcano. To the south of Bezymianny, the peaks of Zimina (3,081 meters above sea level) and Udina (2,923 meters above sea level) volcanoes are just visible above the cloud deck; no historical eruptions are known from either volcanic center. While the large Tobalchik volcano to the southwest (bottom center) is largely formed from a basaltic shield volcano, its highest peak (3,682 meters above sea level) is formed from an older stratovolcano. Tobalchik last erupted in 1976. While this image may look like it was taken from the normal altitude of a passenger jet, the space station was located approximately 417 kilometers above the southeastern Sea of Okhotsk; projected downwards to Earth’s surface, the space station was located over 700 kilometers to the southwest of the volcanoes in the image. The combination of low viewing angle from the orbital outpost, shadows, and height and distance from the volcanoes contributes to the appearance of topographic relief visible in the image.

Small Tharsis Volcano

NASA Technical Reports Server (NTRS)

2004-01-01

30 August 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a small volcano located southwest of the giant volcano, Pavonis Mons, near 2.5oS, 109.4oW. Lava flows can be seen to have emanated from the summit region, which today is an irregularly-shaped collapse pit, or caldera. A blanket of dust mantles this volcano. Dust covers most martian volcanoes, none of which are young or active today. This picture covers an area about 3 km (1.9 mi) across; sunlight illuminates the scene from the left.

Fumarolic activity in marie byrd land, antarctica.

PubMed

Lemasurier, W E; Wade, F A

1968-10-18

Ice towers, probably formed by recent fumarolic activity, have been found around the summit calderas of two volcanoes in Marie Byrd Land. These active (?) volcanoes lie within a broad belt of Mesozoic intrusion and late Cenozoic extrusion that appears to be part of the circum-Pacific orogenic province.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wood, C.A.

Statistical relations have been determined between geometry, volume, slope, and age for 26 circum-Pacific composite (strato) volcanoes. General trends in eruption characteristics, repose periods, flow lengths and petrology are also documented. Few examples of the earliest stages of composite volcano activity are known, perhaps because these small volcanoes are indistinguishable from cinder cones. If cinder cones evolve into composite volcanoes a fundamental change in morphometry, eruption style, and petrology occurs at a basal diameter of 2 km.

Volcanology Curricula Development Aided by Online Educational Resource

NASA Astrophysics Data System (ADS)

Poland, Michael P.; van der Hoeven Kraft, Katrien J.; Teasdale, Rachel

2011-03-01

Using On-Line Volcano Monitoring Data in College and University Courses: The Volcano Exploration Project: Pu`u `Ō`ō (VEPP); Hawaii Volcanoes National Park, Hawaii, 26-30 July 2010; Volcanic activity is an excellent hook for engaging college and university students in geoscience classes. An increasing number of Internet-accessible real-time and near-real time volcano monitoring data are now available and constitute an important resource for geoscience education; however, relatively few data sets are comprehensive, and many lack background information to aid in interpretation. In response to the need for organized, accessible, and well-documented volcano education resources, the U.S. Geological Survey's Hawaiian Volcano Observatory (HVO), in collaboration with NASA and the University of Hawai`i at Manoa, established the Volcanoes Exploration Project: Pu`u `Ō`ō (VEPP). The VEPP Web site (http://vepp.wr.usgs.gov) is an educational resource that provides access, in near real time, to geodetic, seismic, and geologic data from the active Pu`u `Ō`ō eruptive vent on Kilauea volcano, Hawaii, along with background and context information. A strength of the VEPP site is the common theme of the Pu`u `Ō`ō eruption, which allows the site to be revisited multiple times to demonstrate different principles and integrate many aspects of volcanology.

Volcanology curricula development aided by online educational resource

USGS Publications Warehouse

Poland, Michael P.; Van Der Hoeven, Kraft; Teasdale, R.

2011-01-01

Using On-Line Volcano Monitoring Data in College and University Courses: The Volcano Exploration Project: Pu`u `Ō`ō (VEPP); Hawaii Volcanoes National Park, Hawaii, 26–30 July 2010; Volcanic activity is an excellent hook for engaging college and university students in geoscience classes. An increasing number of Internet-accessible real-time and near–real time volcano monitoring data are now available and constitute an important resource for geoscience education; however, relatively few data sets are comprehensive, and many lack background information to aid in interpretation. In response to the need for organized, accessible, and well-documented volcano education resources, the U.S. Geological Survey's Hawaiian Volcano Observatory (HVO), in collaboration with NASA and the University of Hawai`i at Manoa, established the Volcanoes Exploration Project: Pu`u `Ō`ō (VEPP). The VEPP Web site (http://vepp.wr.usgs.gov) is an educational resource that provides access, in near real time, to geodetic, seismic, and geologic data from the active Pu`u `Ō`ō eruptive vent on Kilauea volcano, Hawaii, along with background and context information. A strength of the VEPP site is the common theme of the Pu`u `Ō`ō eruption, which allows the site to be revisited multiple times to demonstrate different principles and integrate many aspects of volcanology.

Eruption history of the Tharsis shield volcanoes, Mars

NASA Technical Reports Server (NTRS)

Plescia, J. B.

1993-01-01

The Tharsis Montes volcanoes and Olympus Mons are giant shield volcanoes. Although estimates of their average surface age have been made using crater counts, the length of time required to build the shields has not been considered. Crater counts for the volcanoes indicate the constructs are young; average ages are Amazonian to Hesperian. In relative terms; Arsia Mons is the oldest, Pavonis Mons intermediate, and Ascreaus Mons the youngest of the Tharsis Montes shield; Olympus Mons is the youngest of the group. Depending upon the calibration, absolute ages range from 730 Ma to 3100 Ma for Arsia Mons and 25 Ma to 100 Ma for Olympus Mons. These absolute chronologies are highly model dependent, and indicate only the time surficial volcanism ceased, not the time over which the volcano was built. The problem of estimating the time necessary to build the volcanoes can be attacked in two ways. First, eruption rates from terrestrial and extraterrestrial examples can be used to calculate the required period of time to build the shields. Second, some relation of eruptive activity between the volcanoes can be assumed, such as they all began at a speficic time or they were active sequentially, and calculate the eruptive rate. Volumes of the shield volcanoes were derived from topographic/volume data.

The relationship between eruptive activity, flank collapse, and sea level at volcanic islands: A long-term (>1 Ma) record offshore Montserrat, Lesser Antilles

NASA Astrophysics Data System (ADS)

Coussens, Maya; Wall-Palmer, Deborah; Talling, Peter. J.; Watt, Sebastian. F. L.; Cassidy, Michael; Jutzeler, Martin; Clare, Michael A.; Hunt, James. E.; Manga, Michael; Gernon, Thomas. M.; Palmer, Martin. R.; Hatter, Stuart. J.; Boudon, Georges; Endo, Daisuke; Fujinawa, Akihiko; Hatfield, Robert; Hornbach, Matthew. J.; Ishizuka, Osamu; Kataoka, Kyoko; Le Friant, Anne; Maeno, Fukashi; McCanta, Molly; Stinton, Adam. J.

2016-07-01

Hole U1395B, drilled southeast of Montserrat during Integrated Ocean Drilling Program Expedition 340, provides a long (>1 Ma) and detailed record of eruptive and mass-wasting events (>130 discrete events). This record can be used to explore the temporal evolution in volcanic activity and landslides at an arc volcano. Analysis of tephra fall and volcaniclastic turbidite deposits in the drill cores reveals three heightened periods of volcanic activity on the island of Montserrat (˜930 to ˜900 ka, ˜810 to ˜760 ka, and ˜190 to ˜120 ka) that coincide with periods of increased volcano instability and mass-wasting. The youngest of these periods marks the peak in activity at the Soufrière Hills volcano. The largest flank collapse of this volcano (˜130 ka) occurred toward the end of this period, and two younger landslides also occurred during a period of relatively elevated volcanism. These three landslides represent the only large (>0.3 km3) flank collapses of the Soufrière Hills edifice, and their timing also coincides with periods of rapid sea level rise (>5 m/ka). Available age data from other island arc volcanoes suggest a general correlation between the timing of large landslides and periods of rapid sea level rise, but this is not observed for volcanoes in intraplate ocean settings. We thus infer that rapid sea level rise may modulate the timing of collapse at island arc volcanoes, but not in larger ocean-island settings.

Lahar-hazard zonation for San Miguel volcano, El Salvador

USGS Publications Warehouse

Major, J.J.; Schilling, S.P.; Pullinger, C.R.; Escobar, C.D.; Chesner, C.A.; Howell, M.M.

2001-01-01

San Miguel volcano, also known as Chaparrastique, is one of many volcanoes along the volcanic arc in El Salvador. The volcano, located in the eastern part of the country, rises to an altitude of about 2130 meters and towers above the communities of San Miguel, El Transito, San Rafael Oriente, and San Jorge. In addition to the larger communities that surround the volcano, several smaller communities and coffee plantations are located on or around the flanks of the volcano, and the PanAmerican and coastal highways cross the lowermost northern and southern flanks of the volcano. The population density around San Miguel volcano coupled with the proximity of major transportation routes increases the risk that even small volcano-related events, like landslides or eruptions, may have significant impact on people and infrastructure. San Miguel volcano is one of the most active volcanoes in El Salvador; it has erupted at least 29 times since 1699. Historical eruptions of the volcano consisted mainly of relatively quiescent emplacement of lava flows or minor explosions that generated modest tephra falls (erupted fragments of microscopic ash to meter sized blocks that are dispersed into the atmosphere and fall to the ground). Little is known, however, about prehistoric eruptions of the volcano. Chemical analyses of prehistoric lava flows and thin tephra falls from San Miguel volcano indicate that the volcano is composed dominantly of basalt (rock having silica content

Satellite observations of the impact of weak volcanic activity on marine clouds

NASA Astrophysics Data System (ADS)

Gassó, Santiago

2008-07-01

Because emissions from weak volcanic eruptions tend to remain in the low troposphere, they may have a significant radiative impact through the indirect effect on clouds. However, this type of volcanic activity is underreported and its global impact has been assessed only by model simulations constrained with very limited observations. First observations of the impact of high-latitude active volcanoes on marine boundary layer clouds are reported here. These observations were made using a combination of standard derived products and visible images from the MODIS, AMSR-E and GOES detectors. Two distinctive effects are identified. When there is an existing boundary layer cloud deck, an increase in cloud brightness and a decrease in both cloud effective radius and liquid water content were observed immediately downwind of the volcanoes. The visible appearance of these "volcano tracks" resembles the effect of man-made ship tracks. When synoptic conditions favor low cloudiness, the volcano plume (or volcano cloud) increases significantly the cloud cover downwind. The volcano cloud can extend for hundreds of kilometers until mixing with background clouds. Unlike violent eruptions, the volcano clouds reported here (the Aleutian Islands in the North Pacific and the South Sandwich Islands in the South Atlantic) have retrieved microphysical properties similar to those observed in ship tracks. However, when comparing the volcano clouds from these two regions, liquid water content can decrease, increase or remain unchanged with respect to nearby unperturbed clouds. These differences suggest that composition at the source, type of eruption and meteorological conditions influence the evolution of the cloud.

Earth Observations taken by the Expedition 31 Crew

NASA Image and Video Library

2012-05-18

ISS031-E-041959 (18 May 2012) --- Alaid Volcano in the Kuril Islands of the Russian Federation is featured in this image photographed by an Expedition 31 crew member on the International Space Station. The Kurils chain extends from the Kamchatka Peninsula to the islands of Japan, and contains numerous active volcanoes along its length. Alaid is the highest (2,339 meters above sea level) volcano in the Kuril chain, as well as being the northernmost. The textbook conic morphology of this stratovolcano is marred only by the summit crater, which is breached to the south (center) and highlighted by snow cover. The volcano rises 3,000 meters directly from the floor of the Sea of Okhotsk, with the uppermost part of the volcanic edifice exposed as an island. Much of the sea surface surrounding the volcano has a silver-gray appearance. This mirror-like appearance is due to sunglint, where light reflects off the sea surface and is scattered directly towards the observer onboard the space station. Sunglint is largely absent from a zone directly to the west of the volcano, most likely due to surface wind or water current patterns that change the roughness?and light scattering properties?of the water surface in this area. Volcanoes in the Kurils, and similar island arcs in the Pacific ?ring of fire?, are fed by magma generated along the boundary between two tectonic plates, where one plate is being driven beneath the other (a process known as subduction). Alaid Volcano has been historically active with the most recent confirmed explosive activity occurring in 1996.

Explosions of andesitic volcanoes in Kamchatka and danger of volcanic ash clouds to aviation

NASA Astrophysics Data System (ADS)

Gordeev, E. I.; Girina, O. A.; Neal, C. A.

2010-12-01

There are 30 active volcanoes in Kamchatka and 4 of them continuously active. The explosions of andesitic volcanoes (Bezymianny and Sheveluch) produce strong and fast ash plumes, which can rich high altitude (up to 15 km) in short time. Bezymianny and Sheveluch are the most active volcanoes of Kamchatka. A growth of the lava dome of Bezymianny into the explosive crater continues from 1956 till present. Nine strong explosive eruptions of the volcano associated with the dome-building activity occurred for last 5 years in: 2005, January 11 and November 30; 2006, May 09 and December 24; 2007, May 11 and October 14-15; 2008, August 19; 2009, December 16-17 and 2010, May 31. Since 1980, a lava dome of Sheveluch has being growing at the bottom of the explosive crater, which has formed as the result of the catastrophic eruption in 1964. Strong explosive eruptions of the volcano associated with the dome-building activity occurred in: 1993, April 22; 2001, May 19-21; 2004, May 09; 2005, February 27 and September 22; 2006, December 25-26; 2007, March 29 and December 19; 2009, April 26-28 and September 10-11. Strong explosive eruption of andesitic volcanoes is the most dangerous for aircraft because in a few hours or days in the atmosphere and the stratosphere can produce about several cubic kilometers of volcanic ash and aerosols. Volcanic ash is an extremely abrasive, as it consists of acute-angled rock fragments and volcanic glass. Due to the high specific surface of andesitic ash particles are capable of retaining an electrostatic charge and absorb droplets of water and corrosive acids. Ash plumes and the clouds, depending on the power of the eruption, the strength and wind speed, can travel thousands of kilometers from the volcano for several days, remaining hazardous to aircraft, as the melting temperature of small particles of ash below the operating temperature of jet engines. To reduce the risk of collision of aircraft with ash clouds of Kamchatkan volcanoes, was created the International KVERT Project, uniting scientists IVS FEB RAS, KB GS RAS and AVO USGS. To solve this problem and provide early warning of air services on the volcanic hazard, scientists analyze the data of seismic, video, visual and satellite monitoring of volcanoes of Kamchatka. In case of ash explosion, cloud or plume detection, information is sending via e-mail operatively to all interested users. Scientists collect all the information (research data, descriptions of eruptions from the literature, observations of tourists, etc.) of the active volcanoes. Based on analysis of historical activity Bezymianny, as well as its continuous monitoring data, scientists of KVERT Project repeatedly predicted the eruption of this volcano. It allowed notifying in time air services of the impending danger of aircraft. For example, in 2001-2010, were predicted 9 of its eruptions (December 16, 2001; December 25, 2002; January 11, 2005; May 9, 2006; May 11, 2007; October 14-15, 2007; August 19, 2008; December 16, 2009; May 31, 2010).

Deformation interplay at Hawaii Island

NASA Astrophysics Data System (ADS)

Shirzaei, M.; Walter, T. R.

2009-12-01

Volcanoes are known to be closely related to the tectonic environment, including vent locations and eruptions resulting from faults and earthquakes. Similarly, adjacent volcanoes interact with each other in time and space, as suggested for the Hawaiian volcanoes Kilauea and Mauna Loa. New satellite radar data imply even more complex deformation interplay in Hawaii than previously thought, involving magma chamber pressure changes, dike intrusions, slow earthquakes and ground subsidence. The affected regions are the Mauna Loa and Kilauea volcano summits, their active rift zones, the island’s unstable southeast flank and even the capital city of Hilo. Based on the data acquired by the European satellite ENVISAT, we present in this work a five-year spatio-temporal analysis of the deformation signals recorded between 2003 and 2008. The data suggests that most of the deformation sources are acting in chorus. The magma intrusion at the Mauna Loa chamber and the intrusion into the Kilauea rift dike are correlated in time while also interacting with gravity-driven flank movement events. Some of the events occur silently underneath the Kilauea south flank, such as slow earthquakes that may largely affect all of the active magmatic systems and reverse their sign of correlation. This study of the interplay between multiple deformations and inherently coupled systems provides a better understanding of Hawaiian volcano activity and may lead to new methods for assessing the hazards that arise during volcano-tectonic activities elsewhere.

Board on Earth Sciences and Resources and its activities

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1995-06-01

The Board on Earth Sciences and Resources (BESR) coordinates, the National Research Council`s advice to the federal government on solid-earth science issues. The board identifies opportunities for advancing basic research and understanding, reports on applications of earth sciences in such areas as disaster mitigation and resource utilization, and analyzes the scientific underpinnings and credibility of earth science information for resource, environmental and other applications and policy decision. Committees operating under the guidance of the Board conducts studies addressing specific issues within the earth sciences. The current committees are as follows: Committee on Geophysical and Environmental Data; Mapping Sciences Committee; Committeemore » on Seismology; Committee on Geodesy; Rediscovering Geography Committee; Committee on Research Programs of the US Bureau of Mines. The following recent reports are briefly described: research programs of the US Bureau of Mines, first assessment 1994; Mount Rainier, active cascade volcano; the national geomagnetic initiative; reservoir class field demonstration program; solid-earth sciences and society; data foundation for the national spatial infrastructure; promoting the national spatial data infrastructure through partnerships; toward a coordinated spatial data infrastructure for the nation; and charting a course into the digital era; guidance to the NOAA`s nautical charting mission.« less

1995 volcanic activity in Alaska and Kamchatka: summary of events and response of the Alaska Volcano Observatory

USGS Publications Warehouse

McGimsey, Robert G.; Neal, Christina A.

1996-01-01

The Alaska Volcano Observatory (AVO) responded to eruptive activity or suspected volcanic activity (SVA) at 6 volcanic centers in 1995: Mount Martin (Katmai Group), Mount Veniaminof, Shishaldin, Makushin, Kliuchef/Korovin, and Kanaga. In addition to responding to eruptive activity at Alaska volcanoes, AVO also disseminated information for the Kamchatkan Volcanic Eruption Response Team (KVERT) on the 1995 eruptions of 2 Russian volcanoes: Bezymianny and Karymsky. This report summarizes volcanic activity in Alaska during 1995 and the AVO response, as well as information on the 2 Kamchatkan eruptions. Only those reports or inquiries that resulted in a "significant" investment of staff time and energy (here defined as several hours or more for reaction, tracking, and follow-up) are included. AVO typically receives dozens of phone calls throughout the year reporting steaming, unusual cloud sightings, or eruption rumors. Most of these are resolved quickly and are not tabulated here as part of the 1995 response record.

Airborne filter pack measurements of S and Cl in the plume of Redoubt Volcano, Alaska February–May 2009

USGS Publications Warehouse

Pfeffer, Melissa; Doukas, Michael P.; Werner, Cynthia A.; Evans, William C.

2013-01-01

Filter pack data from six airborne campaigns at Redoubt Volcano, Alaska are reported here. These measurements provide a rare constraint on Cl output from an andesitic eruption at high emission rate (> 104 t d− 1 SO2). Four S/Cl ratios measured during a period of lava dome growth indicate a depth of last magma equilibration of 2–5 km. The S/Cl ratios in combination with COSPEC SO2 emission rate measurements indicate HCl emission rates of 1500–3600 t d− 1 during dome growth. SO2 and HCl emission rates at Redoubt Volcano correlate with each other and were low prior to the eruption, high during the eruption, and low after the eruption. S/Cl ratios measured by filter pack at andesitic volcanoes have a small range of variance, with no clear trends seen for eruptive versus passive activity. The very few S/Cl ratio measurements by filter pack at andesitic volcanoes are not as predictive of future volcanic activity as has been demonstrated for basaltic volcanoes. This may be because there are so few of these measurements. We have demonstrated it is possible to collect these samples by air between explosions during lava dome-building eruptions. We recommend more filter pack sampling be performed at andesitic volcanoes to determine the technique's utility for volcano monitoring. Filter pack data has been demonstrated to be useful for calculating the depth of magma equilibration at volcanoes including Redoubt Volcano.

The pattern of circumferential and radial eruptive fissures on the volcanoes of Fernandina and Isabela islands, Galapagos

USGS Publications Warehouse

Chadwick, W.W.; Howard, K.A.

1991-01-01

Maps of the eruptive vents on the active shield volcanoes of Fernandina and Isabela islands, Galapagos, made from aerial photographs, display a distinctive pattern that consists of circumferential eruptive fissures around the summit calderas and radial fissures lower on the flanks. On some volcano flanks either circumferential or radial eruptions have been dominant in recent time. The location of circumferential vents outside the calderas is independent of caldera-related normal faults. The eruptive fissures are the surface expression of dike emplacement, and the dike orientations are interpreted to be controlled by the state of stress in the volcano. Very few subaerial volcanoes display a pattern of fissures similar to that of the Galapagos volcanoes. Some seamounts and shield volcanoes on Mars morphologically resemble the Galapagos volcanoes, but more specific evidence is needed to determine if they also share common structure and eruptive style. ?? 1991 Springer-Verlag.

San Cristobal Volcano, Nicaragua

NASA Technical Reports Server (NTRS)

1990-01-01

A white plume of smoke, from San Cristobal Volcano (13.0N, 87.5W) on the western coast of Nicaragua, blows westward along the Nicaraguan coast just south of the Gulf of Fonseca and the Honduran border. San Csistobal is a strato volcano some 1,745 meters high and is frequently active.

Colima Volcano, Mexico

NASA Image and Video Library

1995-10-29

STS073-E-5274 (3 Nov. 1995) --- Colima was photographed with a color Electronic Still Camera (ESC) onboard the Earth-orbiting space shuttle Columbia. The volcano lies due south of Guadalajara and Lake Chapala. It is considered to be one of Mexico's most active and most dangerous volcanoes, lying not far from heavily populated areas.

Volcanism in the Classroom.

ERIC Educational Resources Information Center

Albin, Edward F.

1993-01-01

Presents activities to familiarize junior high school students with the processes behind and reasons for volcanism, which is generally a planet's way of releasing excessive internal heat and pressure. Students participate in the creation of four important volcano-related simulations: a lava flow, a shield volcano, a cinder-cone volcano, and a…

Geology, age, and tectonic setting of the Cretaceous Sliderock Mountain Volcano, Montana

USGS Publications Warehouse

Du Bray, E.A.; Harlan, Stephen S.

1998-01-01

The Sliderock Mountain stratovolcano, part of the Upper Cretaceous continental magmatic arc in southwestern Montana, consists of volcaniclastic strata and basaltic andesite lava flows. An intrusive complex represents the volcano's solidified magma chamber. Compositional diversity within components of the volcano appears to reflect evolution via about 50 percent fractional crystallization involving clinopyroxene and plagioclase. 40Ar/39Ar indicate that the volcano was active about 78?1 Ma.

Linear scaling relationships and volcano plots in homogeneous catalysis - revisiting the Suzuki reaction.

PubMed

Busch, Michael; Wodrich, Matthew D; Corminboeuf, Clémence

2015-12-01

Linear free energy scaling relationships and volcano plots are common tools used to identify potential heterogeneous catalysts for myriad applications. Despite the striking simplicity and predictive power of volcano plots, they remain unknown in homogeneous catalysis. Here, we construct volcano plots to analyze a prototypical reaction from homogeneous catalysis, the Suzuki cross-coupling of olefins. Volcano plots succeed both in discriminating amongst different catalysts and reproducing experimentally known trends, which serves as validation of the model for this proof-of-principle example. These findings indicate that the combination of linear scaling relationships and volcano plots could serve as a valuable methodology for identifying homogeneous catalysts possessing a desired activity through a priori computational screening.

Origin of secondary sulfate minerals on active andesitic stratovolcanoes

USGS Publications Warehouse

Zimbelman, D.R.; Rye, R.O.; Breit, G.N.

2005-01-01

Sulfate minerals in altered rocks on the upper flanks and summits of active andesitic stratovolcanoes result from multiple processes. The origin of these sulfates at five active volcanoes, Citlalte??petl (Mexico), and Mount Adams, Hood, Rainier, and Shasta (Cascade Range, USA), was investigated using field observations, petrography, mineralogy, chemical modeling, and stable-isotope data. The four general groups of sulfate minerals identified are: (1) alunite group, (2) jarosite group, (3) readily soluble Fe- and Al-hydroxysulfates, and (4) simple alkaline-earth sulfates such as anhydrite, gypsum, and barite. Generalized assemblages of spatially associated secondary minerals were recognized: (1) alunite+silica??pyrite??kaolinite?? gypsum??sulfur, (2) jarosite+alunite+silica; (3) jarosite+smectite+silica??pyrite, (4) Fe- and Al-hydroxysulfates+silica, and (5) simple sulfates+silica??Al-hydroxysulfates??alunite. Isotopic data verify that all sulfate and sulfide minerals and their associated alteration assemblages result largely from the introduction of sulfur-bearing magmatic gases into meteoric water in the upper levels of the volcanoes. The sulfur and oxygen isotopic data for all minerals indicate the general mixing of aqueous sulfate derived from deep (largely disproportionation of SO2 in magmatic vapor) and shallow (oxidation of pyrite or H2S) sources. The hydrogen and oxygen isotopic data of alunite indicate the mixing of magmatic and meteoric fluids. Some alunite-group minerals, along with kaolinite, formed from sulfuric acid created by the disproportionation of SO2 in a condensing magmatic vapor. Such alunite, observed only in those volcanoes whose interiors are exposed by erosion or edifice collapse, may have ??34S values that reflect equilibrium (350??50 ??C) between aqueous sulfate and H2S. Alunite with ??34S values indicating disequilibrium between parent aqueous sulfate and H2S may form from aqueous sulfate created in higher level low-temperature environments in which SO2 is scrubbed out by groundwater or where H2S is oxidized. Jarosite-group minerals associated with smectite in only slightly altered volcanic rock are formed largely from aqueous sulfate derived from supergene oxidation of hydrothermal pyrite above the water table. Soluble Al- and Fehydroxysulfates form in low-pH surface environments, especially around fumaroles, and from the oxidation of hydrothermal pyrite. Anhydrite/gypsum, often associated with native sulfur and occasionally with small amounts of barite, also commonly form around fumaroles. Some occurrences of anhydrite/gypsum may be secondary, derived from the dissolution and reprecipitation of soluble sulfate. Edifice collapse may also reveal deep veins of anhydrite/gypsum??barite that formed from the mixing of saline fluids with magmatic sulfate and dilute meteoric water. Alteration along structures associated with both hydrothermal and supergene sulfates, as well as the position of paleo-water tables, may be important factors in edifice collapse and resulting debris flows at some volcanoes. ?? 2004 Elsevier B.V. All rights reserved.

Deployment of broadband seismic and infrasonic networks on Tungurahua and Cotopaxi Volcanoes, Ecuador

NASA Astrophysics Data System (ADS)

Kumagai, H.; Yepes, H.; Vaca, M.; Caceres, V.; Nagai, T.; Yokoe, K.; Imai, T.; Miyakawa, K.; Yamashina, T.; Arrais, S.; Vasconez, F.; Pinajota, E.; Cisneros, C.; Ramos, C.; Paredes, M.; Gomezjurado, L.; Garcia-Aristizabal, A.; Molina, I.; Ramon, P.; Segovia, M.; Palacios, P.; Enriquez, W.; Inoue, I.; Nakano, M.; Inoue, H.

2006-12-01

Tungurahua and Cotopaxi are andesitic active volcanoes in Ecuadorian Andes. Tungurahua continues its eruptive activity since 1999, in which explosive eruptions accompanying pyroclastic flows occurred in July- August, 2006. Cotopaxi is one of the world's highest glacier-clad active volcanoes, and its seismic activity remains high since 2001. To enhance the monitoring capability of these volcanoes, we have installed broadband seismometers (Guralp CMG-40T: 60 s-50 Hz) and infrasonic sensors (ACO TYPE7144/4144: 10 s- 100 Hz) on these volcanoes through the technical cooperation program of Japan International Cooperation Agency (JICA). Three and five stations are currently installed at Tungurahua and Cotopaxi, respectively, and additional two stations will be installed at Tungurahua. Both seismic and infrasonic waveform data at each station are digitized by a Geotech Smart24D datalogger with a sampling frequency of 50 Hz, and transmitted by a digital telemetry system using 2.4 GHz Wireless LAN to the central office in Quito. The Tungurahua's eruptive activity accompanying pyroclastic flows in July-August 2006 was monitored in real-time by the network. The observed waveforms show a wide variety of signatures in response to various eruption styles: intermittent tremor during Strombolian eruptions, five-hour-long continuous strong tremor during heightened eruptions, very-long-period (VLP) seismic signals (10-50 s) associated with pyroclastic flows, and impulsive seismic and infrasonic events of explosions. At Cotopaxi Volcano, VLP signals (2 s) accompanying long- period signals (1-2 Hz) were detected by our network. Similar events occurred in 2002, and are interpreted as gas-release process from magma in an intruded dike beneath Cotopaxi (Molina et al, submitted to JGR). The present observation of the same type of events suggests that the intruded dike is still active beneath Cotopaxi. These signals detected by our networks are highly useful to understand volcanic processes beneath Tungurahua and Cotopaxi, which contribute to improve the monitoring capability of these volcanoes.

Long-term eruptive activity at a submarine arc volcano.

PubMed

Embley, Robert W; Chadwick, William W; Baker, Edward T; Butterfield, David A; Resing, Joseph A; de Ronde, Cornel E J; Tunnicliffe, Verena; Lupton, John E; Juniper, S Kim; Rubin, Kenneth H; Stern, Robert J; Lebon, Geoffrey T; Nakamura, Ko-ichi; Merle, Susan G; Hein, James R; Wiens, Douglas A; Tamura, Yoshihiko

2006-05-25

Three-quarters of the Earth's volcanic activity is submarine, located mostly along the mid-ocean ridges, with the remainder along intraoceanic arcs and hotspots at depths varying from greater than 4,000 m to near the sea surface. Most observations and sampling of submarine eruptions have been indirect, made from surface vessels or made after the fact. We describe here direct observations and sampling of an eruption at a submarine arc volcano named NW Rota-1, located 60 km northwest of the island of Rota (Commonwealth of the Northern Mariana Islands). We observed a pulsating plume permeated with droplets of molten sulphur disgorging volcanic ash and lapilli from a 15-m diameter pit in March 2004 and again in October 2005 near the summit of the volcano at a water depth of 555 m (depth in 2004). A turbid layer found on the flanks of the volcano (in 2004) at depths from 700 m to more than 1,400 m was probably formed by mass-wasting events related to the eruption. Long-term eruptive activity has produced an unusual chemical environment and a very unstable benthic habitat exploited by only a few mobile decapod species. Such conditions are perhaps distinctive of active arc and hotspot volcanoes.

Estimating eruption temperature from thermal emission spectra of lava fountain activity in the Erta'Ale (Ethiopia) volcano lava lake: Implications for observing Io's volcanoes

USGS Publications Warehouse

Davies, A.G.; Keszthelyi, L.; McEwen, A.S.

2011-01-01

We have analysed high-spatial-resolution and high-temporal-resolution temperature measurements of the active lava lake at Erta'Ale volcano, Ethiopia, to derive requirements for measuring eruption temperatures at Io's volcanoes. Lava lakes are particularly attractive targets because they are persistent in activity and large, often with ongoing lava fountain activity that exposes lava at near-eruption temperature. Using infrared thermography, we find that extracting useful temperature estimates from remote-sensing data requires (a) high spatial resolution to isolate lava fountains from adjacent cooler lava and (b) rapid acquisition of multi-color data. Because existing spacecraft data of Io's volcanoes do not meet these criteria, it is particularly important to design future instruments so that they will be able to collect such data. Near-simultaneous data at more than two relatively short wavelengths (shorter than 1 ??m) are needed to constrain eruption temperatures. Resolving parts of the lava lake or fountains that are near the eruption temperature is also essential, and we provide a rough estimate of the required image scale. ?? 2011 by the American Geophysical Union.

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

PubMed

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.

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

PubMed Central

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

2014-01-01

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. PMID:24451461

Measuring thermal budgets of active volcanoes by satellite remote sensing

NASA Technical Reports Server (NTRS)

Glaze, L.; Francis, P. W.; Rothery, D. A.

1989-01-01

Thematic Mapper measurements of the total radiant energy flux Q at Lascar volcano in north Chile for December 1984 are reported. The results are consistent with the earlier suggestion that a lava lake is the source of a reported thermal budget anomaly, and with values for 1985-1986 that are much lower, suggesting that fumarolic activity was then a more likely heat source. The results show that satellite remote sensing may be used to monitor the activity of a volcano quantitatively, in a way not possible by conventional ground studies, and may provide a method for predicting eruptions.

A spaceborne inventory of volcanic activity in Antarctica and southern oceans, 2000-10

USGS Publications Warehouse

Patrick, Matthew R.; Smellie, John L.

2015-01-01

Of the more than twenty historically active volcanoes in Antarctica and the sub-Antarctic region only two, to our knowledge, host any ground-based monitoring instruments. Moreover, because of their remoteness, most of the volcanoes are seldom visited, thus relegating the monitoring of volcanism in this region almost entirely to satellites. In this study, high temporal resolution satellite data from the Hawaii Institute of Geophysics and Planetology's MODVOLC system using MODIS (Moderate Resolution Imaging Spectroradiometer) are complemented with high spatial resolution data (ASTER, or Advanced Spaceborne Thermal Emission and Reflection Radiometer, and similar sensors) to document volcanic activity throughout the region during the period 2000–10. Five volcanoes were observed in eruption (Mount Erebus, Mount Belinda, Mount Michael, Heard Island and McDonald Island), which were predominantly low-level and effusive in nature. Mount Belinda produced tephra, building a cinder cone in addition to an extensive lava field. Five volcanoes exhibited detectable thermal, and presumed fumarolic, activity (Deception, Zavodovski, Candlemas, Bristol, and Bellingshausen islands). A minor eruption reported at Marion Island was not detected in our survey due to its small size. This study also discovered a new active vent on Mount Michael, tracked dramatic vent enlargement on Heard Island, and provides an improved picture of the morphology of some of the volcanoes.

Investigating subsidence at volcanoes in northern California using InSAR

NASA Astrophysics Data System (ADS)

Parker, A. L.; Biggs, J.; Annen, C.; Lu, Z.

2013-12-01

Both Medicine Lake Volcano (MLV) and Lassen Volcanic Center (LVC), northern CA, show signs of subsidence at rates of ~1 cm/yr. Leveling and campaign GPS measurements show that MLV has subsided at a constant rate for over 50 years, making the geodetic history of this volcano unique in both its duration and continuity. Here, we summarise and build upon the existing geodetic records at MLV and LVC, using interferometric synthetic aperture radar (InSAR) to extend the time-series of deformation measurements to 2011. We also use the improved spatial resolution of InSAR measurements to investigate causes of long-term subsidence, providing new insight into magmatic storage conditions at MLV and the timescales of deformation due to cooling and crystallization. A large InSAR dataset has been acquired for the volcanoes of northern CA, but application of the data has been limited by extensive noise and incoherence. We analyse multiple datasets from MLV and LVC and, with the use of multi-temporal InSAR analysis methods (noise-based stacking, π-RATE and StaMPS), demonstrate how InSAR may be used more successfully as a monitoring tool in this region. By comparing InSAR results for MLV to past geodetic studies, we demonstrate that subsidence is on going at ~1 cm/yr with no detectable change in rate. We find that the best fitting source geometry to InSAR data is a sill approximated by a horizontal penny-shaped crack, with radius 2 km and depth 11 km, undergoing volume loss at a rate of -0.0022 km3/yr. We discuss possible source mechanisms of long-term subsidence, investigating volume loss due to cooling and crystallization of an intrusion. We calculate the temperature, melt fraction and volume loss of an intrusion over time using petrological information and a numerical thermal model of heat loss by conduction. The geometry of the intrusion is based upon the depth and radius of the penny-shaped crack model. We run simulations for a range of thicknesses between that of a single intrusion (~50 m) and that of the larger column of intrusive material thought to exist beneath the edifice (~7000 m). Using constraints from the geodetic record, we identify a range of sills with volumes < 10 km3 that can account for the deformation recorded at MLV. We use these models to discuss the timing of intrusion and forecast the total duration of cooling. These processes are also significant at LVC and other Cascade volcanoes, where hydrothermal activity is likely to be driven by heat from magmatic intrusions and the exsolution of volatiles that occurs during cooling and crystallization.

Frequency Based Volcanic Activity Detection through Remotely Sensed Data

NASA Astrophysics Data System (ADS)

Worden, A. K.; Dehn, J.; Webley, P. W.

2015-12-01

Satellite remote sensing has proved to offer a useful and relatively inexpensive method for monitoring large areas where field work is logistically unrealistic, and potentially dangerous. Current sensors are able to detect the majority of explosive volcanic activity; those that tend to effect and represent larger scale changes in the volcanic systems, eventually relating to ash producing periods of extended eruptive activity, and effusive activity. As new spaceborne sensors are developed, the ability to detect activity improves so that a system to gauge the frequency of volcanic activity can be used as a useful monitoring tool. Four volcanoes were chosen for development and testing of a method to monitor explosive activity: Stromboli (Italy); Shishaldin and Cleveland (Alaska, USA); and Karymsky (Kamchatka, Russia). Each volcano studied had similar but unique signatures of pre-cursory and eruptive activity. This study has shown that this monitoring tool could be applied to a wide range of volcanoes and still produce useful and robust data. Our method deals specifically with the detection of small scale explosive activity. The method described here could be useful in an operational setting, especially at remote volcanoes that have the potential to impact populations, infrastructure, and the aviation community. A number of important factors will affect the validity of application of this method. They are: (1) the availability of a continuous and continually populated dataset; (2) appropriate and reasonable sensor resolutions; (3) a recorded history of the volcano's previous activity; and, if available, (4) some ground-based monitoring system. We aim to develop the method further to be able to capture and evaluate the frequency of other volcanic processes such as lava flows, phreatomagmatic eruptions and dome growth and collapse. The work shown here has served to illustrate the capability of this method and monitoring tool for use at remote, un-instrumented volcanoes.

The frequency of explosive volcanic eruptions in Southeast Asia.

PubMed

Whelley, Patrick L; Newhall, Christopher G; Bradley, Kyle E

There are ~750 active and potentially active volcanoes in Southeast Asia. Ash from eruptions of volcanic explosivity index 3 (VEI 3) and smaller pose mostly local hazards while eruptions of VEI ≥ 4 could disrupt trade, travel, and daily life in large parts of the region. We classify Southeast Asian volcanoes into five groups, using their morphology and, where known, their eruptive history and degassing style. Because the eruptive histories of most volcanoes in Southeast Asia are poorly constrained, we assume that volcanoes with similar morphologies have had similar eruption histories. Eruption histories of well-studied examples of each morphologic class serve as proxy histories for understudied volcanoes in the class. From known and proxy eruptive histories, we estimate that decadal probabilities of VEI 4-8 eruptions in Southeast Asia are nearly 1.0, ~0.6, ~0.15, ~0.012, and ~0.001, respectively.

Chasing lava: a geologist's adventures at the Hawaiian Volcano Observatory

USGS Publications Warehouse

Duffield, Wendell A.

2003-01-01

A lively account of the three years (1969-1972) spent by geologist Wendell Duffield working at the Hawaiian Volcano Observatory at Kilauea, one of the world's more active volcanoes. Abundantly illustrated in b&w and color, with line drawings and maps, as well. Volcanologists and general readers alike will enjoy author Wendell Duffield's report from Kilauea--home of Pele, the goddess of fire and volcanoes. Duffield's narrative encompasses everything from the scientific (his discovery that the movements of cooled lava on a lava lake mimic the movements of the earth's crust, providing an accessible model for understanding plate tectonics) to the humorous (his dog's discovery of a snake on the supposedly snake-free island) to the life-threatening (a colleague's plunge into molten lava). This charming account of living and working at Kilauea, one of the world's most active volcanoes, is sure to be a delight.

Seismic activity noted at Medicine Lake Highlands

DOE Office of Scientific and Technical Information (OSTI.GOV)

Blum, D.

1988-12-01

The sudden rumble of earthquakes beneath Medicine Lake Highlands this fall gave geologists an early warning that one of Northern California's volcanoes may be stirring back to life. Researchers stressed that an eruption of the volcano is not expected soon. But the flurry of underground shocks in late September, combined with new evidence of a pool of molten rock beneath the big volcano, has led them to monitor Medicine Lake with new wariness. The volcano has been dormant since 1910, when it ejected a brief flurry of ash - worrying no one. A federal team plans to take measurements ofmore » Medicine Lake, testing for changes in its shape caused by underground pressures. The work is scheduled for spring because snows have made the volcano inaccessible. But the new seismic network is an effective lookout, sensitive to very small increases in activity.« less

Late Holocene history of Chaitén Volcano: new evidence for a 17th century eruption

USGS Publications Warehouse

Lara, Luis E.; Moreno, Rodrigo; Amigo, Álvaro; Hoblitt, Richard P.; Pierson, Thomas C.

2013-01-01

Prior to May 2008, it was thought that the last eruption of Chaitén Volcano occurred more than 5,000 years ago, a rather long quiescent period for a volcano in such an active arc segment. However, increasingly more Holocene eruptions are being identified. This article presents both geological and historical evidence for late Holocene eruptive activity in the 17th century (AD 1625-1658), which included an explosive rhyolitic eruption that produced pumice ash fallout east of the volcano and caused channel aggradation in the Chaitén River. The extents of tephra fall and channel aggradation were similar to those of May 2008. Fine ash, pumice and obsidian fragments in the pre-2008 deposits are unequivocally derived from Chaitén Volcano. This finding has important implications for hazards assessment in the area and suggests the eruptive frequency and magnitude should be more thoroughly studied.

A wireless sensor network for monitoring volcanic tremors

NASA Astrophysics Data System (ADS)

Lopes Pereira, R.; Trindade, J.; Gonçalves, F.; Suresh, L.; Barbosa, D.; Vazão, T.

2013-08-01

Monitoring of volcanic activity is important to learn about the properties of each volcano and provide early warning systems to the population. Monitoring equipment can be expensive and thus, the degree of monitoring varies from volcano to volcano and from country to country, with many volcanoes not being monitored at all. This paper describes the development of a Wireless Sensor Network (WSN) capable of collecting geophysical measurements on remote active volcanoes. Our main goals were to create a flexible, easy to deploy and maintain, adaptable, low-cost WSN for temporary or permanent monitoring of seismic tremor. The WSN enables the easy installation of a sensor array on an area of tens of thousand of m2, allowing the location of the magma movements causing the seismic tremor to be calculated. This WSN can be used by recording data locally for latter analysis or by continuously transmitting it in real time to a remote laboratory for real-time analyses.

Scientists probe Earth’s secrets at the Hawaiian Volcano Observatory

USGS Publications Warehouse

Unger, J.D.

1974-01-01

The Hawaiian Volcano Observatory (HVO) sits on the edge of Kilauea Caldera at the summit of Kilauea Volcao, one of the five volcanoes on the island of Hawaii, the largest island in the Hawaiian Islands chain. Of the five, only Kilauea and Mauna Loa have been active in the past 100 years. Before its last eruption in June 1950, Mauna Loa had erupted more frequently and copiously than Kilauea, but since then only Kilauea has been active. 

Mantle fault zone beneath Kilauea Volcano, Hawaii.

PubMed

Wolfe, Cecily J; Okubo, Paul G; Shearer, Peter M

2003-04-18

Relocations and focal mechanism analyses of deep earthquakes (>/=13 kilometers) at Kilauea volcano demonstrate that seismicity is focused on an active fault zone at 30-kilometer depth, with seaward slip on a low-angle plane, and other smaller, distinct fault zones. The earthquakes we have analyzed predominantly reflect tectonic faulting in the brittle lithosphere rather than magma movement associated with volcanic activity. The tectonic earthquakes may be induced on preexisting faults by stresses of magmatic origin, although background stresses from volcano loading and lithospheric flexure may also contribute.

Leveraging America’s Aircraft Carrier Capabilities. Exploring New Combat and Noncombat Roles and Missions for the U.S. Carrier Fleet

DTIC Science & Technology

2006-01-01

There is always volcanic activity on the Hawaiian Islands. This vignette assumes that the volcano of Kilauea on the Big Island ( Hawaii ) erupts with...has occurred in Hawaii and to the volca- no’s internal configuration that could result in an explosive eruption. Usually, the Kilauea volcano , unlike...seismic activity on Hawaii , the “Big Island,” picks up considerably. In turn, the Kilauea volcano begins a series of vio- lent eruptions of

Mantle fault zone beneath Kilauea Volcano, Hawaii

USGS Publications Warehouse

Wolfe, C.J.; Okubo, P.G.; Shearer, P.M.

2003-01-01

Relocations and focal mechanism analyses of deep earthquakes (???13 kilometers) at Kilauea volcano demonstrate that seismicity is focused on an active fault zone at 30-kilometer depth, with seaward slip on a low-angle plane, and other smaller, distinct fault zones. The earthquakes we have analyzed predominantly reflect tectonic faulting in the brittle lithosphere rather than magma movement associated with volcanic activity. The tectonic earthquakes may be induced on preexisting faults by stresses of magmatic origin, although background stresses from volcano loading and lithospheric flexure may also contribute.

Prokaryotic diversity of an active mud volcano in the Usu City of Xinjiang, China.

PubMed

Yang, Hong-Mei; Lou, Kai; Sun, Jian; Zhang, Tao; Ma, Xiao-Long

2012-02-01

The Usu mud volcanoes are the largest group of terrestrial mud volcanoes in China. The volcanoes are located in a typical arid and semi-arid region, and the group consists of 36 erupting active mud volcanoes. In this study, the prokaryotic diversity and community structure in the sediment of an active mud volcano were investigated by constructing bacterial and archaeal clone libraries of the 16S rRNA gene. A total of 100 bacterial and 100 archaeal clones were analysed and found to comprise 11 and 7 distinct phylotypes, respectively. The bacterial phylotypes were classified into three phyla (Proteobacteria, Actinobacteria, and Fusobacteria). Of these, Proteobacteria were the most abundant bacterial group, with Deltaproteobacteria dominating the sediment community, and these were affiliated with the order Desulfuromonadales. The archaeal phylotypes were all closely related to uncultivated species, and the majority of the members were related to the orders Methanosarcinales and Halobacteriales of the Euryarchaeota originating from methane hydrate bearing or alkaline sediments. The rest of the archaeal phylotypes belonged to the phylum Crenarchaeota, with representatives from similar habitats. These results suggested that a large number of novel microbial groups and potential methanogenesis may exist in this unique ecosystem. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Geologic map of the Lacamas Creek quadrangle, Clark County, Washington

USGS Publications Warehouse

Evarts, R.C.

2006-01-01

The Lacamas Creek 7.5 minute quadrangle is in southwestern Washington, approximately 25 km northeast of Portland, Oregon, along the eastern margin of the Portland Basin, which is part of the Puget-Willamette Lowland that separates the Cascade Range from the Oregon Coast Range. Since late Eocene time, the Cascade Range has been the locus of an episodically active volcanic arc associated with underthrusting of oceanic lithosphere beneath the North American continent along the Cascadia Subduction Zone. Lava flows that erupted early in the history of the arc underlie the eastern half of the Lacamas Creek quadrangle, forming a dissected terrain, with elevations as high as 2050 ft (625 m), that slopes irregularly but steeply to the southwest. These basalt and basaltic andesite flows erupted in early Oligocene time from one or more vents located outside the map area. The flows dip gently (less than 5 degrees) west to southwest. In the western part of the map area, volcanic bedrock is unconformably overlain by middle Miocene to early Pleistocene(?) sediments that accumulated as the Portland Basin subsided. These sediments consist mostly of detritus carried into the Portland Basin by the ancestral Columbia River. Northwest-striking faults offset the Paleogene basin floor as well as the lower part of the basin fill. In middle Pleistocene time, basalt and basaltic andesite erupted from three small volcanoes in the southern half of the map area. These vents are in the northern part of the Boring volcanic field, which comprises several dozen late Pliocene and younger monogenetic volcanoes scattered throughout the greater Portland region. In latest Pleistocene time, the Missoula floods of glacial-outburst origin inundated the Portland Basin. The floods deposited poorly sorted gravels in the southwestern part of the Lacamas Creek quadrangle that grade northward into finer grained sediments. This map is a contribution to a program designed to improve geologic knowledge of the Portland Basin region of the Pacific Northwest urban corridor, the densely populated Cascadia forearc region of western Washington and Oregon. More detailed information on the bedrock and surficial geology of the basin and its surrounding area is necessary to refine assessments of seismic risk, ground-failure hazards and resource availability in this rapidly growing region.

Complex frequency analysis Tornillo earthquake Lokon Volcano in North Sulawesi period 1 January-17 March 2016

NASA Astrophysics Data System (ADS)

Hasanah, Intan; Syahbana, Devy Kamil; Santoso, Agus; Palupi, Indriati Retno

2017-07-01

Indonesia consists of 127 active volcanoes, that causing Indonesia has a very active seismic activity. The observed temporal variation in the complex frequency analysis of Tornillo earthquake in this study at Lokon Volcano, North Sulawesi occured during the period from January 1 to March 17, 2016. This research was conducted using the SOMPI method, with parameters of complex frequency is oscillation frequency (f) and decay coda character of wave (Q Factor). The purpose of this research was to understand the condition of dynamics of fluids inside Lokon Volcano in it's period. The analysis was based on the Sompi homogeneous equation Auto-Regressive (AR). The results of this study were able to estimate the dynamics of fluids inside Lokon Volcano and identify the content of the fluid and dynamics dimension crust. Where the Tornillo earthquake in this period has a value of Q (decay waves) are distributed under 200 and frequency distributed between 3-4 Hz. Tornillo earthquake was at a shallow depth of less than 2 km and paraded to the Tompaluan Crater. From the analysis of complex frequencies, it can be estimated if occured an eruption at Lokon Volcano in it's period, the estimated type of eruption was phreatic eruption. With an estimated composition of the fluid in the form of Misty Gas a mass fraction of gas ranging between 0-100%. Another possible fluid contained in Lokon Volcano is water vapor with the gas volume fraction range 10-90%.

Swarms of small earthquakes on Marapi Volcano, West Sumatra, Indonesia: are these precursors to explosion event?

NASA Astrophysics Data System (ADS)

Hidayat, D.; Patria, C.; Adi, S.; Gunawan, H.; Taisne, B.; Nurfiani, D.; Tan, C. T.

2016-12-01

Marapi Volcano's activity is characterized by Strombolian to small Vulcanian explosions with occasional VEI 2 producing tephra and pyroclastic flows. Currently in collaboration between Earth Observatory of Singapore (EOS) and Centre for Volcanology and Geological Hazard Mitigation (CVGHM) the volcano is seismically monitored with 7 broadband stations, and 2 short-period stations. In addition, we deployed 2 tiltmeters and an experimental soil CO2 sensor. These stations are telemetered by 5.8GHz radio to Marapi Observatory Post where data are archived and displayed for Marapi observers for their daily volcano activity monitoring work. We also archive the data in the EOS and CVGHM main offices. Data are being utilized by volcano scientists of CVGHM and researchers in both institutes as well as university students in and around them. We presented seismic earthquake sequences (swarm) prior to small explosion on Marapi in July 2016. These earthquakes are small, better identified after the deployment of seismic stations at summit, and located at depths < 1km near the volcano active vents. Similar swarms occurred prior to small explosions of Marapi. We also presented VLP-LP signals associated with an explosion which can be explained as volumetric change of sub-vertical crack at depth similar to the occurrence of small earthquake swarms. Our study attempt to understand the state of the volcano based on monitoring data and enable us to better estimate the hazards associated with future small explosions or eruptions.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Davisson, M.L.; Rose, T.P.

Quaternary-age volcanic peaks of Mt. Lassen, Mt. Shasta, and Medicine Lake Volcano preferentially recharge and transport large volumes of annual precipitation into mega- scale channels hosted in underlying volcanic layers. At the terminus of laterally extensive lava flows, or in deep incisions of these layers, groundwater emerges as large volume cold springs. The combined discharge of these springs contributes half the annual storage capacity of Shasta Reservoir, and is utilized to generate 2000 gigawatts of hydroelectric power each year. Moreover, the springs provide a natural habitat for many rare and endangered species. In the Hat Creek Valley, located north ofmore » Mt. Lassen, Rose et al. (1996) showed that the low d 18 O discharge of large volume springs at Rising River and Crystal Lake originates from snow melt in the high elevation, high precipitation region surrounding Lassen Peak. Groundwater transport in this basin is enhanced by the occurrence of the Quaternary Hat Creek basalt flow, which extends nearly the entire length of Hat Creek Valley. In contrast, the d 18 O values of large- volume springs that discharge in the Mt. Shasta region indicate a larger percentage of local recharge at lower elevations since the high elevation snow melt on the volcano is depleted by >1 per mil relative to the largest springs. The d 18 O value of the Fall River Springs (FRS) system is similar to small springs that occur at high elevations on Medicine Lake Volcano. The large volume of the FRS discharge coupled with a lack of surficial drainages in this area indicates that a large percentage of the annual precipitation over an ~750 mi 2 area of the Medicine Lake volcanic plateau goes to recharge the FRS aquifer system. Groundwater transport to the FRS is enhanced by the occurrence of the 10 kyr Giant Crater lava flow, a single geologic unit that extends from the base of Medicine Lake Volcano to the FRS. many of the large volume springs in the southern Cascade Range. For example, the radiocarbon concentration in Rising River Springs is 80 pmc, which indicates at least 20% of its dissolved inorganic carbon is derived from a magmatic source in the Lassen region. The radiocarbon activity in the FRS is as low as 73 pmc, indicating a minimum contribution of 27% magmatic CO2 from Medicine Lake volcano. Magmatic CO2 fluxes in the Shasta region are highest around the base of the volcano, where low- volume, CO2 -rich, 14 C- absent soda springs occur. Relatively large quantities of magmatic CO2 are observed in the Big Springs of the McCloud River, which have a d 18 O signature consistent with low elevation recharge in the Shasta region. relative to Mt. Lassen and Medicine Lake Volcano reflect significant differences in the geomorphology of the volcanoes. In particular, the composite nature of the Shasta stratocone tends to limit the depth of groundwater recharge, confining the majority of groundwater flow to the shallowest layers, which tend to be of more local extent. The lower permeability of the composite cone also acts as a trap for magmatic CO2 emissions, generally limiting the gas discharge to localized fracture zones at lower elevations. At Mt. Lassen and Medicine Lake Volcano, groundwater recharge occurs primarily at high elevations, along vertical fracture systems with high permeabilities. These features, combined with laterally extensive basalt flows, act to focus groundwater transport deeper and over longer lateral distances. The magmatic CO2 dissolution process probably occurs in close proximity to the geothermal systems at Lassen and Medicine Lake, where CO2 gas escaping along deep fractures encounters downward percolating groundwater.« less

Earth observations taken from Space Shuttle Columbia during STS-78 mission

NASA Image and Video Library

1996-07-01

STS078-742-004 (20 June - 7 July 1996) --- This is a north-looking perspective of the major volcanoes of the Cascade Mountains of southern Washington and northern Oregon. With the Earth limb in the upper left corner of the photo, the large mountain at the top right, or northern part of the photo, is Mt. Rainier. The next snow covered area to the south east of Mt. Rainier is Gilbert Point. Mt. Adams is the larger peak, south-southeast of Mt. Rainier, Mt. St. Helens is the gray patch in the center of the photo, west of Mt. Adams. Mt. St. Helens erupted on May 18, 1980, removing 1,300 feet of the 9,677-ft. volcano. The eruption toppled trees with a searing, stone-filled 275-mile-per-hour wind over an area of more than 150 square miles. This area, now referred to as the "blast zone", can be easily spotted in this view. NASA scientists say that natural regrowth of vegetation within the blast zone is progressing at a rapid rate, especially on the outer fringes and in the protected valleys. Many fir trees have grown to heights exceeding 20 feet in a little over 12 years. A large lava dome within the crater of the volcano has grown to a height of over 1,000 feet since the 1980 eruption. The next three snow covered peaks are Mt. Hood, Mt. Jefferson and the Three Sisters all located in Oregon.

Mercury and Iodine systematics of volcanic arc fluids

NASA Astrophysics Data System (ADS)

Varekamp, J. C.; Kading, T.; Fehn, U.; Lu, Z.

2008-12-01

The mantle has low Mercury and Iodine concentrations, but these elements occur in volcanic gases and hydrothermal fluids at ppb (Hg) and ppm (Iodine) levels. Possibly, the Hg and Iodine concentrations in volcanic fluids reflect subducted sediment sources in arc magmas. Iodine is a biophilic element, and I129/I values indicate that subducted sediment (especially organic matter) is an important Iodine source for arc magmas. It is uncertain if this is true for Hg as well, although in the surface environment Hg is commonly associated with organic matter. We present 60 new analyses of Hg and I in fluids from volcanoes in Central America, New Zealand, Japan, and the Cascades. A first assessment suggests that Iodine is released to some degree in the early stage of subduction in the forearc, whereas Hg may be released largely below the main volcanic arc. Isotope and trace element signatures of volcanic rocks of the investigated volcanoes show no simple correlation with Hg or Iodine abundances. The acid hot spring fluids of Copahue volcano (Argentina) carried ~ 200 ppt Hg in January 1999, ~80 ppt Hg in March 2008, and 90 ppt Hg in the crater lake in March 1997. The dissolved Hg fluxes from the Copahue hydrothermal system are ~300 gr Hg/year in 1999 and ~130 gr Hg/year in 2008. The bulk hydrothermal Hg flux (particle bound+dissolved) in 2008 was ~ 350 gr Hg/year. The potential Mercury evasion from these hydrothermal spring fluids into the air has not yet been incorporated in these estimates.

Magma plumbing system and seismicity of an active mid-ocean ridge volcano.

PubMed

Schmid, Florian; Schlindwein, Vera; Koulakov, Ivan; Plötz, Aline; Scholz, John-Robert

2017-02-20

At mid-ocean ridges volcanism generally decreases with spreading rate but surprisingly massive volcanic centres occur at the slowest spreading ridges. These volcanoes can host unexpectedly strong earthquakes and vigorous, explosive submarine eruptions. Our understanding of the geodynamic processes forming these volcanic centres is still incomplete due to a lack of geophysical data and the difficulty to capture their rare phases of magmatic activity. We present a local earthquake tomographic image of the magma plumbing system beneath the Segment 8 volcano at the ultraslow-spreading Southwest Indian Ridge. The tomography shows a confined domain of partial melt under the volcano. We infer that from there melt is horizontally transported to a neighbouring ridge segment at 35 km distance where microearthquake swarms and intrusion tremor occur that suggest ongoing magmatic activity. Teleseismic earthquakes around the Segment 8 volcano, prior to our study, indicate that the current magmatic spreading episode may already have lasted over a decade and hence its temporal extent greatly exceeds the frequent short-lived spreading episodes at faster opening mid-ocean ridges.

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

PubMed

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

2017-10-03

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

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

NASA Astrophysics Data System (ADS)

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

2015-12-01

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

Sheet intrusions and deformation of Piton des Neiges, and their implication for the volcano-tectonics of La Réunion

NASA Astrophysics Data System (ADS)

Chaput, Marie; Famin, Vincent; Michon, Laurent

2017-10-01

To understand the volcano-tectonic history of Piton des Neiges (the dormant volcano of La Réunion), we measured in the field the orientation of sheeted intrusions and deformation structures, and interpreted the two datasets separately with a paleostress inversion. Results show that the multiple proposed rift zones may be simplified into three trends: (1) a N30°E, 5 km wide linear rift zone running to the south of the edifice, active in the shield building (≥ 2.48-0.43 Ma) and terminal stages (190-22 ka); (2) a curved N110 to N160°E rift zone, widening from 5 km to 10 km toward the NW flank, essentially active during the early emerged shield building (≥ 1.3 Ma); and (3) two sill zones, ≤ 1 km thick in total, in the most internal parts of the volcano, active in the shield building and terminal stages. In parallel, deformation structures reveal that the tectonics of the edifice consisted in three end-member stress regimes sharing common stress axes: (1) NW-SE extension affecting in priority the south of the edifice near the N30°E rift zone; (2) NNE-SSW extension on the northern half of the volcano near the N110-160°E rift zone; (3) compression occurring near the sill zones, with a NE-SW or NW-SE maximum principal stress. These three stress regimes are spatially correlated and mechanically compatible with the injection trends. Combined together, our data show that the emerged Piton des Neiges underwent sector spreading delimited by perpendicular rift zones, as observed on Piton de la Fournaise (the active volcano of La Réunion). Analogue experiments attribute such sector spreading to brittle edifices built on a weaker substratum. We therefore conclude that La Réunion volcanoes are both brittle, as opposed to Hawaiian volcanoes or Mount Etna whose radial spreading is usually attributed to a ductile body within the edifices.

Interpreting Low Spatial Resolution Thermal Data from Active Volcanoes on Io and the Earth

NASA Technical Reports Server (NTRS)

Keszthelyi, L.; Harris, A. J. L.; Flynn, L.; Davies, A. G.; McEwen, A.

2001-01-01

The style of volcanism was successfully determined at a number of active volcanoes on Io and the Earth using the same techniques to interpret thermal remote sensing data. Additional information is contained in the original extended abstract.

Measuring Gases Using Drones at Turrialba Volcano, Costa Rica

NASA Astrophysics Data System (ADS)

Stix, J.; Alan, A., Jr.; Corrales, E.; D'Arcy, F.; de Moor, M. J.; Diaz, J. A.

2016-12-01

We are currently developing a series of drones and associated instrumentation to study Turrialba volcano in Costa Rica. This volcano has shown increasing activity during the last 20 years, and the volcano is currently in a state of heightened unrest as exemplified by recent explosive activity in May-August 2016. The eruptive activity has made the summit area inaccessible to normal gas monitoring activities, prompting development of new techniques to measure gas compositions. We have been using two drones, a DJI Spreading Wings S1000 octocopter and a Turbo Ace Matrix-i quadcopter, to airlift a series of instruments to measure volcanic gases in the plume of the volcano. These instruments comprise optical and electrochemical sensors to measure CO2, SO2, and H2S concentrations which are considered the most significant species to help forecast explosive eruptions and determine the relative proportions of magmatic and hydrothermal components in the volcanic gas. Additionally, cameras and sensors to measure air temperature, relative humidity, atmospheric pressure, and GPS location are included in the package to provide meteorological and geo-referenced information to complement the concentration data and provide a better picture of the volcano from a remote location. The integrated payloads weigh 1-2 kg, which can typically be flown by the drones in 10-20 minutes at altitudes of 2000-4000 meters. Preliminary tests at Turrialba in May 2016 have been very encouraging, and we are in the process of refining both the drones and the instrumentation packages for future flights. Our broader goals are to map gases in detail with the drones in order to make flux measurements of each species, and to apply this approach at other volcanoes.

Earth observation taken by the Expedition 29 crew

NASA Image and Video Library

2011-10-07

ISS029-E-020003 (7 Oct. 2011) --- Parinacota Volcano in the Chile-Bolivia border region, South America is featured in this image photographed by an Expedition 29 crew member on the International Space Station. Volcan Parinacota (?flamingo lake? in the regional Aymara language) is a potentially active stratovolcano located on the Altiplano, a high plateau situated within the Andes Mountains of west-central South America. While no direct observations of eruptive activity are recorded, surface exposure age-dating of lava flows suggests that activity occurred as recently as 290 AD approximately 300 years, according to scientists. Local Aymara stories also suggest that the volcano has erupted during the past 1,000 years. This detailed photograph highlights the symmetrical cone of Parinacota, with its well-developed summit crater (elevation 6,348 meters above sea level) at center. Dark brown to dark gray surfaces to the east and west of the summit include lava flows, pyroclastic deposits, and ash. A companion volcano, Pomerape, is located across a low saddle to the north ? scientists believe this volcano last erupted during the Pleistocene Epoch (extending from approximately 3 million to 12,000 years ago). The summits of both volcanoes are covered by white permanent snowpack and small glaciers. Together, the two volcanoes form the Nevados de Payachata volcanic area. Eruptive activity at Parinacota has directly influenced development of the local landscape beyond the emplacement of volcanic deposits ? approximately 8,000 years ago the western flank of the volcano collapsed, creating a debris avalanche that traveled 22 kilometers to the west. This debris avalanche blocked drainages, leading to the formation of Lake Chungara to the south (upper right). The uneven, hummocky surface of the debris avalanche deposit provides ample catchments for water, as evidenced by the numerous small ponds and Cotacotani Lake to the west.

Intrusion Triggering of Explosive Eruptions: Lessons Learned from EYJAFJALLAJÖKULL 2010 Eruptions and Crustal Deformation Studies

NASA Astrophysics Data System (ADS)

Sigmundsson, F.; Hreinsdottir, S.; Hooper, A. J.; Arnadottir, T.; Pedersen, R.; Roberts, M. J.; Oskarsson, N.; Auriac, A.; Decriem, J.; Einarsson, P.; Geirsson, H.; Hensch, M.; Ofeigsson, B. G.; Sturkell, E. C.; Sveinbjornsson, H.; Feigl, K.

2010-12-01

Gradual inflation of magma chambers often precedes eruptions at highly active volcanoes. During eruptions, rapid deflation occurs as magma flows out and pressure is reduced. Less is known about the deformation style at moderately active volcanoes, such as Eyjafjallajökull, Iceland, where an explosive summit eruption of trachyandesite beginning on 14 April 2010 caused exceptional disruption to air traffic. This eruption was preceded by an effusive flank eruption of olivine basalt from 20 March - 12 April 2010. Geodetic and seismic observations revealed the growth of an intrusive complex in the roots of the volcano during three months prior to eruptions. After initial horizontal growth, modelling indicates both horizontal and sub-vertical growth in three weeks prior the first eruption. The behaviour is attributed to subsurface variations in crustal stress and strength originating from complicated volcano foundations. A low-density layer may capture magma allowing pressure to build before an intrusion can ascend towards higher levels. The intrusive complex was formed by olivine basalt as erupted on the volcano flank 20 March - 12 April; the intrusive growth halted at the onset of this eruption. Deformation associated with the eruption onset was minor as the dike had reached close to the surface in the days before. Isolated eruptive vents opening on long-dormant volcanoes may represent magma leaking upwards from extensive pre-eruptive intrusions formed at depth. A deflation source activated during the summit eruption of trachyandesite is distinct from, and adjacent to, all documented sources of inflation in the volcano roots. Olivine basalt magma which recharged the volcano appears to have triggered the summit eruption, although the exact mode of triggering is uncertain. Scenarios include stress triggering or propagation of olivine basalt into more evolved magma. The trachyandesite includes crystals that can be remnants of minor recent intrusion of olivine basalt. Alternatively, mixing of larger portion of olivine basalt with more evolved magma may have occurred. Intrusions may lead to eruptions not only when they find their way to the surface; at Eyjafjallajökull our observation show how primitive melts in an intrusive complex active since 1992 catalyzed an explosive eruption of trachyandesite. Eyjafjallajökull’s behaviour can be attributed to its off-rift setting with a relatively cold subsurface structure and limited magma at shallow depth, as may be typical for moderately active volcanoes. Clear signs of volcanic unrest signals over years to weeks may indicate reawakening of such volcanoes whereas immediate short-term precursors may be subtle and difficult to detect.

Thermal precursors in satellite images of the 1999 eruption of Shishaldin Volcano

NASA Astrophysics Data System (ADS)

Dehn, Jonathan; Dean, Kenneson; Engle, Kevin; Izbekov, Pavel

2002-07-01

Shishaldin Volcano, Unimak Island Alaska, began showing signs of thermal unrest in satellite images on 9 February 1999. A thermal anomaly and small steam plume were detected at the summit of the volcano in short-wave thermal infrared AVHRR (advanced very high resolution radiometer) satellite data. This was followed by over 2 months of changes in the observed thermal character of the volcano. Initially, the thermal anomaly was only visible when the satellite passed nearly directly over the volcano, suggesting a hot source deep in the central crater obscured from more oblique satellite passes. The "zenith angle" needed to see the anomaly increased with time, presumably as the thermal source rose within the conduit. Based on this change, an ascent rate of ca. 14 m per day for the thermal source was estimated, until it reached the summit on around 21 March. It is thought that Strombolian activity began around this time. The precursory activity culminated in a sub-Plinian eruption on 19 April, ejecting ash to over 45,000 ft. (13,700 m). The thermal energy output through the precursory period was calculated based on geometric constraints unique to Shishaldin. These calculations show fluctuations that can be tied to changes in the eruptive character inferred from seismic records and later geologic studies. The remote location of this volcano made satellite images a necessary observation tool for this eruption. To date, this is the longest thermal precursory activity preceding a sub-Plinian eruption recorded by satellite images in the region. This type of thermal monitoring of remote volcanoes is central in the efforts of the Alaska Volcano Observatory to provide timely warnings of volcanic eruption, and mitigate their associated hazards to air-traffic and local residents.

Earth Observation

NASA Image and Video Library

2013-10-29

ISS037-E-022473 (29 Oct. 2013) --- La Malinche Volcano, Mexico is featured in this image photo graphed by an Expedition 37 crew member on the International Space Station. Located approximately 30 kilometers to the northeast of the city of Puebla, the summit of Volcan la Malinche rises to an elevation of 4,461 meters above sea level. This detailed photograph highlights the snow-dusted summit, and the deep canyons that cut into the flanks of this eroded stratovolcano. La Malinche has not been historically active, but radiometric dating of volcanic rocks and deposits associated with the structure indicate a most recent eruption near the end of the 12th century. NASA scientists cite evidence that lahars, or mudflows, associated with an eruption about 3,100 years ago, affected Pre-Columbian settlements in the nearby Puebla basin. The volcano is enclosed within La Malinche National Park situated within parts of the states of Puebla and Tlaxcala; extensive green forest cover is visible on the lower flanks of the volcano. Access to the volcano is available through roadways, and it is frequently used as a training peak by climbers prior to attempting higher summits. The rectangular outlines of agricultural fields are visible forming an outer ring around the forested area. While the volcano appears to be quiescent, its relatively recent (in geological terms) eruptive activity, and location within the Trans-Mexican Volcanic Belt– a tectonically active region with several current and historically active volcanoes including Popocatepetl to the west and Pico de Orizaba to the east - suggests that future activity is still possible and could potentially pose a threat to the nearby city of Puebla.

Potential ash impact from Antarctic volcanoes: Insights from Deception Island's most recent eruption.

PubMed

Geyer, A; Marti, A; Giralt, S; Folch, A

2017-11-28

Ash emitted during explosive volcanic eruptions may disperse over vast areas of the globe posing a threat to human health and infrastructures and causing significant disruption to air traffic. In Antarctica, at least five volcanoes have reported historic activity. However, no attention has been paid to the potential socio-economic and environmental consequences of an ash-forming eruption occurring at high southern latitudes. This work shows how ash from Antarctic volcanoes may pose a higher threat than previously believed. As a case study, we evaluate the potential impacts of ash for a given eruption scenario from Deception Island, one of the most active volcanoes in Antarctica. Numerical simulations using the novel MMB-MONARCH-ASH model demonstrate that volcanic ash emitted from Antarctic volcanoes could potentially encircle the globe, leading to significant consequences for global aviation safety. Results obtained recall the need for performing proper hazard assessment on Antarctic volcanoes, and are crucial for understanding the patterns of ash distribution at high southern latitudes with strong implications for tephrostratigraphy, which is pivotal to synchronize palaeoclimatic records.

A wireless sensor network for monitoring volcano-seismic signals

NASA Astrophysics Data System (ADS)

Lopes Pereira, R.; Trindade, J.; Gonçalves, F.; Suresh, L.; Barbosa, D.; Vazão, T.

2014-12-01

Monitoring of volcanic activity is important for learning about the properties of each volcano and for providing early warning systems to the population. Monitoring equipment can be expensive, and thus the degree of monitoring varies from volcano to volcano and from country to country, with many volcanoes not being monitored at all. This paper describes the development of a wireless sensor network (WSN) capable of collecting geophysical measurements on remote active volcanoes. Our main goals were to create a flexible, easy-to-deploy and easy-to-maintain, adaptable, low-cost WSN for temporary or permanent monitoring of seismic tremor. The WSN enables the easy installation of a sensor array in an area of tens of thousands of m2, allowing the location of the magma movements causing the seismic tremor to be calculated. This WSN can be used by recording data locally for later analysis or by continuously transmitting it in real time to a remote laboratory for real-time analyses. We present a set of tests that validate different aspects of our WSN, including a deployment on a suspended bridge for measuring its vibration.

Why did we lose the 59 climbers in 2014 Ontake Volcano Eruption?

NASA Astrophysics Data System (ADS)

Kimata, F.

2015-12-01

The first historical eruption at Ontake volcano, central Japan was in 1979, and it was a phreatic eruption. Until then, most Japanese volcanologists understood that Ontake is a dormant or an extinct volcano. Re-examination of active volcanoes was done after the eruption.After the first historical eruption in 1979, two small eruptions are repeated in 1991 and 2007. Through the three eruptions, nobody has got injured. The last eruption on September 27, 2014, we lost 65 people included missing. Because it was fine weekend and there were many climbers on the summit. The eruption was almost at lunchtime. Clearly, casualties by tsunamis are inhabitants along the coastlines, and casualties by eruption are visitors not inhabitants around the volcano. Basically, visitors have small information of Ontake volcano. After the accident, one mountain guide tells us that we never have long broken such as lunch around the summit, because an active creator is close, and they are afraid of the volcano gas accidents. All casualties by eruption were lost their lives in the area of 1.0 km distance from the 2014 creators. In 2004 Sumatra Earthquake Tsunami, we could not recognize the tsunami inspiration between the habitants in Banda Aceh, Sumatra. They have no idea of tsunami, and they called "Rising Sea" never"Tsunami". As the result, they lost many habitants close to the coast. In 2011 Tohoku Earthquake Tsunami, when habitants felt strong shaking close to coast, they understood the tsunami coming. 0ver 50 % habitants decide to evacuate from the coast. However, 20-30 % habitants believe in themselves no tsunami attacking for them. As a result we lost many habitants. Additionally, the tsunami height was higher than broadcasting one by JMA. According to the results of the questionnaire survey in climbers or bereaved families of the eruption day on Ontake volcano (Shinano Mainich Newspaper, 2015), 39 % of them were climbing no understand of "Ontake active volcano". Moreover, only 10-20 % of them was understanding some seismic activities in September. I met some bereaved family, and I understand the climbers are almost beginners. On the one hand, JMA, government and local governments never understand the experience of climbers of Ontake volcano. It was the main cause of the 2014 Ontake eruption accident.

Recurrent patterns in fluid geochemistry data prior to phreatic eruptions

NASA Astrophysics Data System (ADS)

Rouwet, Dmitri; Sandri, Laura; Todesco, Micol; Tonini, Roberto; Pecoraino, Giovannella; Diliberto, Iole Serena

2016-04-01

Not all volcanic eruptions are magma-driven: the sudden evaporation and expansion of heated groundwater may cause phreatic eruptions, where the magma involvement is absent or negligible. Active crater lakes top some of the volcanoes prone to phreatic activity. This kind of eruption may occur suddenly, and without clear warning: on September 27, 2014 a phreatic eruption of Ontake, Japan, occurred without timely precursors, killing 57 tourists near the volcano summit. Phreatic eruptions can thus be as fatal as higher VEI events, due to the lack of recognised precursory signals, and because of their explosive and violent nature. In this study, we tackle the challenge of recognising precursors to phreatic eruptions, by analysing the records of two "phreatically" active volcanoes in Costa Rica, i.e. Poás and Turrialba, respectively with and without a crater lake. These volcanoes cover a wide range of time scales in eruptive behaviour, possibly culminating into magmatic activity, and have a long-term multi-parameter dataset mostly describing fluid geochemistry. Such dataset is suitable for being analysed by objective pattern recognition techniques, in search for recurrent schemes. The aim is to verify the existence and nature of potential precursory patterns, which will improve our understanding of phreatic events, and allow the assessment of the associated hazard at other volcanoes, such as Campi Flegrei or Vulcano, in Italy. Quantitative forecast of phreatic activity will be performed with BET_UNREST, a Bayesian Event Tree tool recently developed within the framework of FP7 EU VUELCO project. The study will combine the analysis of fluid geochemistry data with pattern recognition and phreatic eruption forecast on medium and short-term. The study will also provide interesting hints on the features that promote or hinder phreatic activity in volcanoes that host well-developed hydrothermal circulation.

Space Radar Image of Colombian Volcano

NASA Image and Video Library

1999-01-27

This is a radar image of a little known volcano in northern Colombia. The image was acquired on orbit 80 of space shuttle Endeavour on April 14, 1994, by NASA Spaceborne Imaging Radar C/X-Band Synthetic Aperture Radar SIR-C/X-SAR. The volcano near the center of the image is located at 5.6 degrees north latitude, 75.0 degrees west longitude, about 100 kilometers (65 miles) southeast of Medellin, Colombia. The conspicuous dark spot is a lake at the bottom of an approximately 3-kilometer-wide (1.9-mile) volcanic collapse depression or caldera. A cone-shaped peak on the bottom left (northeast rim) of the caldera appears to have been the source for a flow of material into the caldera. This is the northern-most known volcano in South America and because of its youthful appearance, should be considered dormant rather than extinct. The volcano's existence confirms a fracture zone proposed in 1985 as the northern boundary of volcanism in the Andes. The SIR-C/X-SAR image reveals another, older caldera further south in Colombia, along another proposed fracture zone. Although relatively conspicuous, these volcanoes have escaped widespread recognition because of frequent cloud cover that hinders remote sensing imaging in visible wavelengths. Four separate volcanoes in the Northern Andes nations of Colombia and Ecuador have been active during the last 10 years, killing more than 25,000 people, including scientists who were monitoring the volcanic activity. Detection and monitoring of volcanoes from space provides a safe way to investigate volcanism. The recognition of previously unknown volcanoes is important for hazard evaluations because a number of major eruptions this century have occurred at mountains that were not previously recognized as volcanoes. http://photojournal.jpl.nasa.gov/catalog/PIA01722

Record of late holocene debris avalanches and lahars at Iliamna Volcano, Alaska

USGS Publications Warehouse

Waythomas, C.F.; Miller, T.P.; Beget, J.E.

2000-01-01

Iliamna Volcano is a 3053-meter high, glaciated stratovolcano in the southern Cook Inlet region of Alaska and is one of seven volcanoes in this region that have erupted multiple times during the past 10,000 yr. Prior to our studies of Iliamna Volcano, little was known about the frequency, magnitude, and character of Holocene volcanic activity. Here we present geologic evidence of the most recent eruptive activity of the volcano and provide the first outline of Late Holocene debris-avalanche and lahar formation. Iliamna has had no documented historical eruptions but our recent field investigations indicate that the volcano has erupted at least twice in the last 300 yr. Clay-rich lahar deposits dated by radiocarbon to ???1300 and ???90 yr BP are present in two major valleys that head on the volcano. These deposits indicate that at least two large, possibly deep-seated, flank failures of the volcanic edifice have occurred in the last 1300 yr. Noncohesive lahar deposits likely associated with explosive pyroclastic eruptions date to 2400-1300,>1500,???300, and <305 yr BP. Debris-avalanche deposits from recent and historical small-volume slope failures of the hydrothermally altered volcanic edifice cover most of the major glaciers on the volcano. Although these deposits consist almost entirely of hydrothermally altered rock debris and snow and ice, none of the recently generated debris avalanches evolved to lahars. A clay-rich lahar deposit that formed <90??60 radiocarbon yr BP and entered the Johnson River Valley southeast of the volcano cannot be confidently related to an eruption of Iliamna Volcano, which has had no known historical eruptions. This deposit may record an unheralded debris avalanche and lahar. ?? 2000 Elsevier Science B.V. All rights reserved.

Vertical Motions of Oceanic Volcanoes

NASA Astrophysics Data System (ADS)

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

2006-12-01

Oceanic volcanoes offer abundant evidence of changes in their elevations through time. Their large-scale motions begin with a period of rapid subsidence lasting hundreds of thousands of years caused by isostatic compensation of the added mass of the volcano on the ocean lithosphere. The response is within thousands of years and lasts as long as the active volcano keeps adding mass on the ocean floor. Downward flexure caused by volcanic loading creates troughs around the growing volcanoes that eventually fill with sediment. Seismic surveys show that the overall depression of the old ocean floor beneath Hawaiian volcanoes such as Mauna Loa is about 10 km. This gross subsidence means that the drowned shorelines only record a small part of the total subsidence the islands experienced. In Hawaii, this history is recorded by long-term tide-gauge data, the depth in drill holes of subaerial lava flows and soil horizons, former shorelines presently located below sea level. Offshore Hawaii, a series of at least 7 drowned reefs and terraces record subsidence of about 1325 m during the last half million years. Older sequences of drowned reefs and terraces define the early rapid phase of subsidence of Maui, Molokai, Lanai, Oahu, Kauai, and Niihau. Volcanic islands, such as Maui, tip down toward the next younger volcano as it begins rapid growth and subsidence. Such tipping results in drowned reefs on Haleakala as deep as 2400 m where they are tipped towards Hawaii. Flat-topped volcanoes on submarine rift zones also record this tipping towards the next younger volcano. This early rapid subsidence phase is followed by a period of slow subsidence lasting for millions of years caused by thermal contraction of the aging ocean lithosphere beneath the volcano. The well-known evolution along the Hawaiian chain from high to low volcanic island, to coral island, and to guyot is due to this process. This history of rapid and then slow subsidence is interrupted by a period of minor uplift lasting a few hundred thousand years as the island migrates over a broad flexural arch related to isostatic compensation of a nearby active volcano. The arch is located about 190±30 km away from the center of volcanic activity and is also related to the rejuvenated volcanic stage on the islands. Reefs on Oahu that are uplifted several tens of m above sea level are the primary evidence for uplift as the islands over-ride the flexural arch. At the other end of the movement spectrum, both in terms of magnitude and length of response, are the rapid uplift and subsidence that occurs as magma is accumulated within or erupted from active submarine volcanoes. These changes are measured in days to years and are of cm to m variation; they are measured using leveling surveys, tiltmeters, EDM and GPS above sea level and pressure gauges and tiltmeters below sea level. Other acoustic techniques to measure such vertical movement are under development. Elsewhere, evidence for subsidence of volcanoes is also widespread, ranging from shallow water carbonates on drowned Cretaceous guyots, to mapped shoreline features, to the presence of subaerially-erupted (degassed) lavas on now submerged volcanoes. Evidence for uplift is more limited, but includes makatea islands with uplifted coral reefs surrounding low volcanic islands. These are formed due to flexural uplift associated with isostatic loading of nearby islands or seamounts. In sum, oceanic volcanoes display a long history of subsidence, rapid at first and then slow, sometimes punctuated by brief periods of uplift due to lithospheric loading by subsequently formed nearby volcanoes.

Volcanoes of the World: Reconfiguring a scientific database to meet new goals and expectations

NASA Astrophysics Data System (ADS)

Venzke, Edward; Andrews, Ben; Cottrell, Elizabeth

2015-04-01

The Smithsonian Global Volcanism Program's (GVP) database of Holocene volcanoes and eruptions, Volcanoes of the World (VOTW), originated in 1971, and was largely populated with content from the IAVCEI Catalog of Volcanoes of Active Volcanoes and some independent datasets. Volcanic activity reported by Smithsonian's Bulletin of the Global Volcanism Network and USGS/SI Weekly Activity Reports (and their predecessors), published research, and other varied sources has expanded the database significantly over the years. Three editions of the VOTW were published in book form, creating a catalog with new ways to display data that included regional directories, a gazetteer, and a 10,000-year chronology of eruptions. The widespread dissemination of the data in electronic media since the first GVP website in 1995 has created new challenges and opportunities for this unique collection of information. To better meet current and future goals and expectations, we have recently transitioned VOTW into a SQL Server database. This process included significant schema changes to the previous relational database, data auditing, and content review. We replaced a disparate, confusing, and changeable volcano numbering system with unique and permanent volcano numbers. We reconfigured structures for recording eruption data to allow greater flexibility in describing the complexity of observed activity, adding in the ability to distinguish episodes within eruptions (in time and space) and events (including dates) rather than characteristics that take place during an episode. We have added a reference link field in multiple tables to enable attribution of sources at finer levels of detail. We now store and connect synonyms and feature names in a more consistent manner, which will allow for morphological features to be given unique numbers and linked to specific eruptions or samples; if the designated overall volcano name is also a morphological feature, it is then also listed and described as that feature. One especially significant audit involved re-evaluating the categories of evidence used to include a volcano in the Holocene list, and reviewing in detail the entries in low-certainty categories. Concurrently, we developed a new data entry system that may in the future allow trusted users outside of Smithsonian to input data into VOTW. A redesigned website now provides new search tools and data download options. We are collaborating with organizations that manage volcano and eruption databases, physical sample databases, and geochemical databases to allow real-time connections and complex queries. VOTW serves the volcanological community by providing a clear and consistent core database of distinctly identified volcanoes and eruptions to advance goals in research, civil defense, and public outreach.

Different types of small volcanos on Venus

NASA Technical Reports Server (NTRS)

Slyuta, E. N.; Shalimov, I. V.; Nikishin, A. M.

1992-01-01

One of the studies of volcanic activity on Venus is the comparison of that with the analogous volcanic activity on Earth. The preliminary report of such a comparison and description of a small cluster of small venusian volcanos is represented in detail in this paper.

Geologic Map of the Bodie Hills Volcanic Field, California and Nevada: Anatomy of Miocene Cascade Arc Magmatism in the Western Great Basin

NASA Astrophysics Data System (ADS)

John, D. A.; du Bray, E. A.; Blakely, R. J.; Box, S.; Fleck, R. J.; Vikre, P. G.; Rytuba, J. J.; Moring, B. C.

2011-12-01

The Bodie Hills Volcanic Field (BHVF) is a >700 km2, long-lived (~9 Ma) but episodic, Miocene eruptive center in the southern part of the ancestral Cascade magmatic arc. A 1:50,000-scale geologic map based on extensive new mapping, combined with 40Ar/39Ar dates, geochemical data, and detailed gravity and aeromagnetic surveys, defines late Miocene magmatic and hydrothermal evolution of the BHVF and contrasts the subduction-related BHVF with the overlying, post-subduction, bimodal Plio-Pleistocene Aurora Volcanic Field (AVF). Important features of the BHVF include: Eruptions occurred during 3 major eruptive stages: dominantly trachyandesite stratovolcanoes (~14.7 to 12.9 Ma), mixed silicic trachyandesite, dacite, and rhyolite (~11.3 to 9.6 Ma), and dominantly silicic trachyandesite to dacite domes (~9.2 to 8.0 Ma). Small rhyolite domes were emplaced at ~6 Ma. Trachyandesitic stratovolcanoes with extensive debris flow aprons form the outer part of BHVF, whereas silicic trachyandesite to rhyolite domes are more centrally located. Geophysical data suggest that many BHVF volcanoes have shallow plutonic roots that extend to depths ≥1-2 km below the surface, and much of the Bodie Hills may be underlain by low density plutons presumably related to BHVF volcanism. BHVF rocks contain ~50 to 78% SiO2 (though few rocks have <55% SiO2), have high-K calc-alkaline compositions, and have negative Ti-P-Nb-Ta anomalies and high Ba/Nb, Ba/Ta, and La/Nb typical of subduction-related continental margin arcs. BHVF rocks include mafic trachyandesite/basaltic andesite (50%), silicic trachyandesite-dacite (40%), and rhyolite (10%). Approximately circular, polygenetic volcanoes and scarcity of dikes suggest a low differential horizontal stress field during formation of BHVF. Subduction ceased beneath the Bodie Hills at ~10 Ma, but the composition and eruptive style of volcanism continued unchanged for 2 Ma. However, kinematic data for veins and faults in mining districts suggest a change in the stress field from transtensional to extensional approximately coincident with cessation of subduction. The Bodie Hills are flanked to the east, north, and west by sedimentary basins that began to form in the late Miocene (locally >11 Ma). Fine to coarse sedimentary deposits within the BHVF include stream deposits in channels that cut across the hills and were partly filled by ~9.4 Ma Eureka Valley Tuff erupted 20 km to the northwest. Shallow dips and preservation of primary volcanic morphologies indicate only minor post-volcanic extension of the Bodie Hills. Hydrothermal activity alternated with volcanism, forming both large epithermal Au-Ag vein deposits and large areas of strongly altered but weakly mineralized rock. Compared to AVF, BHVF had a higher average eruptive rate, includes more phenocryst-rich lavas, and formed diverse types of volcanoes inferred to be underlain by large plutons. Consequently, the 2 volcanic fields were probably associated with substantially different magmatic processes and formed in different stress regimes.

Renewed unrest at Mount Spurr Volcano, Alaska

USGS Publications Warehouse

Power, John A.

2004-01-01

The Alaska Volcano Observatory (AVO),a cooperative program of the U.S. Geological Survey, the University of Alaska Fairbanks Geophysical Institute, and the Alaska Division of Geological and Geophysical Surveys, has detected unrest at Mount Spurr volcano, located about 125 km west of Anchorage, Alaska, at the northeast end of the Aleutian volcanic arc.This activity consists of increased seismicity melting of the summit ice cap, and substantial rates of C02 and H2S emission.The current unrest is centered beneath the volcano's 3374-m-high summit, whose last known eruption was 5000–6000 years ago. Since then, Crater Peak, 2309 m in elevation and 4 km to the south, has been the active vent. Recent eruptions occurred in 1953 and 1992.

Application of photogrammetry to the study of volcano-glacier interactions on Mount Wrangell, Alaska

NASA Technical Reports Server (NTRS)

Benson, C. S.; Follett, A. B.

1986-01-01

Most Alaskan volcanoes are glacier covered and provide excellent opportunities to study interactions between glaciers and volcanoes. The present paper is concerned with such a study, taking into account the Mt. Wrangell (4317 m) which is the northernmost active volcano (solfatara activity) on the Pacific Rim (62 deg N; 144 deg W). While the first photographs on the summit of Mt. Wrangell were published more than 75 years ago, research there began in 1953 and 1954. Satellite images reveal activity at the summit of Mt. Wrangell. However, the resolution is not sufficient for conducting important measurements regarding ice volume losses. For this reason, vertical aerial photographs of the summit were obtained, and a field trip to the summit was conducted. Aspects of photogrammetry are discussed, taking into account questions of ground control, aerial photography, topographic mapping, digital cross sections, and orthophotos.

Mt. Erebus, Antarctica

NASA Image and Video Library

2016-01-15

This image from NASA Terra spacecraft shows Mount Erebus, the world southernmost historically active volcano, overlooking the McMurdo research station on Ross Island. The 3794-m-high Erebus is the largest of three major volcanoes forming the crudely triangular Ross Island. An elliptical 500 x 600 m wide, 110-m-deep crater truncates the summit and contains an active lava lake within a 250-m-wide, 100-m-deep inner crater. The glacier-covered volcano was erupting when first sighted by Captain James Ross in 1841. Continuous lava-lake activity with minor explosions, punctuated by occasional larger strombolian explosions that eject bombs onto the crater rim, has been documented since 1972, but has probably been occurring for much of the volcano's recent history. The image was acquired December 31, 2013, covers an area of 63 x 73 km, and is located at 77.5 degrees south, 167.1 degrees east. http://photojournal.jpl.nasa.gov/catalog/PIA20239

Risk-Free Volcano Observations Using an Unmanned Autonomous Helicopter: seismic observations near the active vent of Sakurajima volcano, Japan

NASA Astrophysics Data System (ADS)

Ohminato, T.; Kaneko, T.; Koyama, T.; Yasuda, A.; Watanabe, A.; Takeo, M.; Honda, Y.; Kajiwara, K.; Kanda, W.; Iguchi, M.; Yanagisawa, T.

2010-12-01

Observations in the vicinity of summit area of active volcanoes are important not only for understanding physical processes in the volcanic conduit but also for eruption prediction and volcanic hazards mitigation. It is, however, challenging to install observation sensors near active vents because of the danger of sudden eruptions. We need safe and efficient ways of installing sensors near the summit of active volcanoes. We have been developing an volcano observation system based on an unmanned autonomous vehicle (UAV) for risk-free volcano observations. Our UAV is an unmanned autonomous helicopter manufactured by Yamaha-Motor Co., Ltd. The UAV is 3.6m long and weighs 84kg with maximum payload of 10kg. The UAV can aviate autonomously along a previously programmed path within a meter accuracy using real-time kinematics differential GPS equipment. The maximum flight time and distance from the operator are 90 minutes and 5km, respectively. We have developed various types of volcano observation techniques adequate for the UAV, such as aeromagnetic survey, taking infrared and visible images from onboard high-resolution cameras, volcanic ash sampling in the vicinity of active vents. Recently, we have developed an earthquake observation module (EOM), which is exclusively designed for the UAV installation in the vicinity of active volcanic vent. In order to meet the various requirements for UAV installation, the EOM is very compact, light-weight (5-6kg), and is solar-powered. It is equipped with GPS for timing, a communication device using cellular-phone network, and triaxial accelerometers. Our first application of the EOM installation using the UAV is one of the most active volcanoes in Japan, Sakurajima volcano. Since 2006, explosive eruptions have been continuing at the reopened Showa crater at the eastern flank near the summit of Sakurajima. Entering the area within 2 km from the active craters is prohibited, and thus there were no observation station in the vicinity of active vents at the summit area. From November 2nd to 12th, 2009, we could successfully install four EOMs in the summit area within 2km from the active craters by using the UAV. Although the state of communication was not perfect since the installation points were outside of the service area of the cellular-phone network, we succeeded in retrieving the seismic waveform data accompanying moderate eruptions at Showa crater. Except for contamination by the mechanical resonance of the frame of EOM around 35 Hz, the recorded waveforms of the explosive eruptions are as good as the best permanent stations in Sakurajima. Preliminary results of the analyses show that the source location distribution of the explosion earthquakes at Showa crater is improved by the inclusion of the near source stations newly installed by using the UAV.

Monitoring an EGS injection at Newberry Volcano using Magnetotelluric dimensionality analysis

NASA Astrophysics Data System (ADS)

Bowles-martinez, E.; Schultz, A.; Rose, K.; Urquhart, S.

2016-12-01

The sensitivity of magnetotelluric (MT) data to the presence of electrically conductive subsurface features makes it applicable for determining the extent of injected fluids in enhanced geothermal systems (EGS). We use MT to monitor fluid injection during tests of a proposed EGS site at Newberry Volcano in Central Oregon, USA. Newberry is a large shield volcano located where fault systems of the northern Basin and Range meet the Cascade Arc and the high lava plains. Its strong potential for geothermal energy has made it a target for energy exploration for over 40 years. MT measurements were made before, during, and after an EGS stimulation in 2014 in an effort to detect subsurface pathways taken by fluids that are attributable to stimulation. We begin by creating a baseline model from inverting over 200 wideband MT stations located in the western half of the volcano. This model is constrained by well logs, as well as by high resolution gravity and seismic velocity modeling. Our model shows conductive regions associated with the caldera's ring fault, likely showing where hydrothermal fluids or their mineral alteration products are present. However, as this is an EGS study, we are interested in detecting fluid intrusion into hot, dry rock. Therefore, our primary target is a resistive zone on the western flank of Newberry volcano that is interpreted as a series of hot intrusive sequences. Well bottom temperatures in this area have been measured in excess of 300 °C. The stimulation's effect on resistivity is subtle, in part because the injected fluid is fresh groundwater, the injected volume is modest, and the target depth is 2,000-3,000 m below ground level. We found that it is advantageous to look at the impedance tensor data directly to detect injected fluids. Because fluids and their associated change in resistivity are expected to be concentrated around the injection well, the injection will exhibit a highly three-dimensional resistivity structure. Therefore, we examine the impedance tensor for changes in dimensionality to mark the arrival of injected fluids. We then present a method of inverting MT data for changes in impedance rather than for resistivity.

Remotely Sensed Density Measurements of Volcanic Sulfur Dioxide Plumes Using a Spectral Long Wave Infrared Imager

DTIC Science & Technology

2002-09-01

USGS). (Tilling, R., Heliker, C., and Wright, T., “ Eruptions of Hawaiian Volcanoes ”) The mission of HVO is to monitor Hawaii’s Mauna Loa and Kilauea ...Hendley, J., “Living on Active Volcanoes ”) Hawaii’s Kilauea Volcano is unique in its long-term (1983 – present), nearly continuous eruptive ...monitoring the gas emission process of Kilauea Volcano . During periods of sustained eruption , Kilauea emits about 2,000 tons of sulfur dioxide gas (SO2

Aerogeophysical measurements of collapse-prone hydrothermally altered zones at Mount Rainier volcano.

PubMed

Finn, C A; Sisson, T W; Deszcz-Pan, M

2001-02-01

Hydrothermally altered rocks can weaken volcanoes, increasing the potential for catastrophic sector collapses that can lead to destructive debris flows. Evaluating the hazards associated with such alteration is difficult because alteration has been mapped on few active volcanoes and the distribution and severity of subsurface alteration is largely unknown on any active volcano. At Mount Rainier volcano (Washington, USA), collapses of hydrothermally altered edifice flanks have generated numerous extensive debris flows and future collapses could threaten areas that are now densely populated. Preliminary geological mapping and remote-sensing data indicated that exposed alteration is contained in a dyke-controlled belt trending east-west that passes through the volcano's summit. But here we present helicopter-borne electromagnetic and magnetic data, combined with detailed geological mapping, to show that appreciable thicknesses of mostly buried hydrothermally altered rock lie mainly in the upper west flank of Mount Rainier. We identify this as the likely source for future large debris flows. But as negligible amounts of highly altered rock lie in the volcano's core, this might impede collapse retrogression and so limit the volumes and inundation areas of future debris flows. Our results demonstrate that high-resolution geophysical and geological observations can yield unprecedented views of the three-dimensional distribution of altered rock.

Prediction of ground motion and dynamic stress change in Baekdusan (Changbaishan) volcano caused by a North Korean nuclear explosion.

PubMed

Hong, Tae-Kyung; Choi, Eunseo; Park, Seongjun; Shin, Jin Soo

2016-02-17

Strong ground motions induce large dynamic stress changes that may disturb the magma chamber of a volcano, thus accelerating the volcanic activity. An underground nuclear explosion test near an active volcano constitutes a direct treat to the volcano. This study examined the dynamic stress changes of the magma chamber of Baekdusan (Changbaishan) that can be induced by hypothetical North Korean nuclear explosions. Seismic waveforms for hypothetical underground nuclear explosions at North Korean test site were calculated by using an empirical Green's function approach based on a source-spectral model of a nuclear explosion; such a technique is efficient for regions containing poorly constrained velocity structures. The peak ground motions around the volcano were estimated from empirical strong-motion attenuation curves. A hypothetical M7.0 North Korean underground nuclear explosion may produce peak ground accelerations of 0.1684 m/s(2) in the horizontal direction and 0.0917 m/s(2) in the vertical direction around the volcano, inducing peak dynamic stress change of 67 kPa on the volcano surface and ~120 kPa in the spherical magma chamber. North Korean underground nuclear explosions with magnitudes of 5.0-7.6 may induce overpressure in the magma chamber of several tens to hundreds of kilopascals.

Aerogeophysical measurements of collapse-prone hydrothermally altered zones at Mount Rainier volcano

USGS Publications Warehouse

Finn, C.A.; Sisson, T.W.; Deszcz-Pan, M.

2001-01-01

Hydrothermally altered rocks can weaken volcanoes, increasing the potential for catastrophic sector collapses that can lead to destructive debris flows1. Evaluating the hazards associated with such alteration is difficult because alteration has been mapped on few active volcanoes1-4 and the distribution and severity of subsurface alteration is largely unknown on any active volcano. At Mount Rainier volcano (Washington, USA), collapses of hydrothermally altered edifice flanks have generated numerous extensive debris flows5,6 and future collapses could threaten areas that are now densely populated7. Preliminary geological mapping and remote-sensing data indicated that exposed alteration is contained in a dyke-controlled belt trending east-west that passes through the volcano's summit3-5,8. But here we present helicopter-borne electromagnetic and magnetic data, combined with detailed geological mapping, to show that appreciable thicknesses of mostly buried hydrothermally altered rock lie mainly in the upper west flank of Mount Rainier. We identify this as the likely source for future large debris flows. But as negligible amounts of highly altered rock lie in the volcano's core, this might impede collapse retrogression and so limit the volumes and inundation areas of future debris flows. Our results demonstrate that high-resolution geophysical and geological observations can yield unprecedented views of the three-dimensional distribution of altered rock.

Eruption Forecasting in Alaska: A Retrospective and Test of the Distal VT Model

NASA Astrophysics Data System (ADS)

Prejean, S. G.; Pesicek, J. D.; Wellik, J.; Cameron, C.; White, R. A.; McCausland, W. A.; Buurman, H.

2015-12-01

United States volcano observatories have successfully forecast most significant US eruptions in the past decade. However, eruptions of some volcanoes remain stubbornly difficult to forecast effectively using seismic data alone. The Alaska Volcano Observatory (AVO) has responded to 28 eruptions from 10 volcanoes since 2005. Eruptions that were not forecast include those of frequently active volcanoes with basaltic-andesite magmas, like Pavlof, Veniaminof, and Okmok volcanoes. In this study we quantify the success rate of eruption forecasting in Alaska and explore common characteristics of eruptions not forecast. In an effort to improve future forecasts, we re-examine seismic data from eruptions and known intrusive episodes in Alaska to test the effectiveness of the distal VT model commonly employed by the USGS-USAID Volcano Disaster Assistance Program (VDAP). In the distal VT model, anomalous brittle failure or volcano-tectonic (VT) earthquake swarms in the shallow crust surrounding the volcano occur as a secondary response to crustal strain induced by magma intrusion. Because the Aleutian volcanic arc is among the most seismically active regions on Earth, distinguishing distal VT earthquake swarms for eruption forecasting purposes from tectonic seismicity unrelated to volcanic processes poses a distinct challenge. In this study, we use a modified beta-statistic to identify pre-eruptive distal VT swarms and establish their statistical significance with respect to long-term background seismicity. This analysis allows us to explore the general applicability of the distal VT model and quantify the likelihood of encountering false positives in eruption forecasting using this model alone.

Stratigraphic framework of Holocene volcaniclastic deposits, Akutan Volcano, east-central Aleutian Islands, Alaska

USGS Publications Warehouse

Waythomas, C.F.

1999-01-01

Akutan Volcano is one of the most active volcanoes in the Aleutian arc, but until recently little was known about its history and eruptive character. Following a brief but sustained period of intense seismic activity in March 1996, the Alaska Volcano Observatory began investigating the geology of the volcano and evaluating potential volcanic hazards that could affect residents of Akutan Island. During these studies new information was obtained about the Holocene eruptive history of the volcano on the basis of stratigraphic studies of volcaniclastic deposits and radiocarbon dating of associated buried soils and peat. A black, scoria-bearing, lapilli tephra, informally named the 'Akutan tephra,' is up to 2 m thick and is found over most of the island, primarily east of the volcano summit. Six radiocarbon ages on the humic fraction of soil A-horizons beneath the tephra indicate that the Akutan tephra was erupted approximately 1611 years B.P. At several locations the Akutan tephra is within a conformable stratigraphic sequence of pyroclastic-flow and lahar deposits that are all part of the same eruptive sequence. The thickness, widespread distribution, and conformable stratigraphic association with overlying pyroclastic-flow and lahar deposits indicate that the Akutan tephra likely records a major eruption of Akutan Volcano that may have formed the present summit caldera. Noncohesive lahar and pyroclastic-flow deposits that predate the Akutan tephra occur in the major valleys that head on the volcano and are evidence for six to eight earlier Holocene eruptions. These eruptions were strombolian to subplinian events that generated limited amounts of tephra and small pyroclastic flows that extended only a few kilometers from the vent. The pyroclastic flows melted snow and ice on the volcano flanks and formed lahars that traveled several kilometers down broad, formerly glaciated valleys, reaching the coast as thin, watery, hyperconcentrated flows or water floods. Slightly cohesive lahars in Hot Springs valley and Long valley could have formed from minor flank collapses of hydrothermally altered volcanic bedrock. These lahars may be unrelated to eruptive activity.

Comparison of diffuse CO2 degassing at Miravalles and Rincón de la Vieja volcanoes (Guanacaste Province, Costa Rica)

NASA Astrophysics Data System (ADS)

Liegler, A.; Bakkar Hindeleh, H.; Deering, C. D.; Fentress, S. E.

2015-12-01

Volcanic gas emissions are a key component for monitoring volcanic activity, magmatic input of volatiles to the atmosphere and the assessment of geothermal potential in volcanic regions. Diffuse soil degassing has been shown to represent a major part of volcanic gas emissions. However, this type of gas emission has not yet been quantified in the Guanacaste province of Costa Rica; a region of the country with several large, active or dormant volcanoes. We conducted the first study of diffuse CO2 degassing at Rincón de la Vieja and Miravalles volcanoes, both located in Guanacaste. Diffuse degassing was measured using the accumulation chamber method to quantify CO2 flux in regions where hydrothermal surface features indicate anomalous activity. The total diffuse carbon dioxide flux estimated at Miravalles in two areas, together roughly 2 km2 in size, was 135 t/day and in several areas at Rincón de la Vieja a minimum of 4 t/day. Comparatively low flux values and a very local concentration (few m2) of CO2 flux were observed at the active Rincón de la Vieja volcano, compared to the dormant Miravalles volcano, where significant soil flux was found over extended areas, not only around vents. Our assessment of the origin of these differences leads to two possibilities depending on if the surface features on the two volcanoes are fed by a common hydrothermal system or two separate ones. In the former case, the different intensity of diffuse CO2 flux could indicate a different degassing behavior and stronger concentration of gas emissions at the active vent areas at Rincon de la Vieja. In the latter case, where the hydrothermal systems are not linked, the amount of CO2 degassed through the flanks of the volcanoes could indicate that different physical and chemical conditions are governing the degassing of the two systems.

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

NASA Astrophysics Data System (ADS)

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

2017-11-01

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

Volcano spacings and lithospheric attenuation in the Eastern Rift of Africa

NASA Technical Reports Server (NTRS)

Mohr, P. A.; Wood, C. A.

1976-01-01

The Eastern Rift of Africa runs the gamut of crustal and lithospheric attenuation from undeformed shield through attenuated rift margin to active neo-oceanic spreading zones. It is therefore peculiarly well suited to an examination of relationships between volcano spacings and crust/lithosphere thickness. Although lithospheric thickness is not well known in Eastern Africa, it appears to have direct expression in the surface spacing of volcanoes for any given tectonic regime. This applies whether the volcanoes are essentially basaltic, silicic, or alkaline-carbonatitic. No evidence is found for control of volcano sites by a pre-existing fracture grid in the crust.

Volcano monitoring at the U.S. Geological Survey's Hawaiian Volcano Observatory

USGS Publications Warehouse

Heliker, Christina C.; Griggs, J. D.; Takahashi, T. Jane; Wright, Thomas L.; Spall, Henry

1986-01-01

The island of Hawaii has one of the youngest landscapes on Earth, formed by frequent addition of new lava to its surface.  Because Hawaiian are generally nonexplosive and easily accessible, the island has long attracted geologists interested in studying the extraordinary power of volcanic eruptions.  The U.S. Geological Survey's Hawaiian Volcano Observatory (HVO), now nearing its 75th anniversary. has been in the forefront of volcanology since the 1900's.  This issue of Earthquakes and volcanoes is devoted to the work of the Observatory and its role in studying the most recent eruptions of Hawaii's two currently active volcanoes, Kilauea and Mauna Loa.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hochstein, M.P.; Sudarman, Sayogi

There are at least 30 high temperatures systems (with inferred reservoir temperatures > 200 C) along the active Sumatra Arc that transfer heat from crustal intrusions to the surface. These systems, together with eleven active volcanoes, five degassing volcanoes and one caldera volcano (Lake Toba), are controlled by the Sumatra Fault Zone, an active mega shear zone that follows the median axis of the arc. At least half of the active and degassing volcanoes are associated with volcanic geothermal reservoirs containing magmatic gases and acid fluids. Large, low temperature resources exist in the Tertiary sedimentary basins of east Sumatra (back-arcmore » region), where anomalously higher thermal gradients (up to 8 C/100 m) have been measured. Volcanic activity was not continuous during the Cenozoic; subduction and arc volcanism probably decreased after the Eocene as a result of a clockwise rotation of Sumatra. In the Late Miocene, subduction started again, and andesitic volcanism reached a new peak of intensity in the Pliocene and has been continuous ever since. Rhyolitic volcanism, which has produced voluminous ignimbrite flows, began later (Pliocene/Pleistocene). All known rhyolitic centers associated with ignimbrite flows appear to lie along the Sumatra Fault Zone.« less

U.S. Geological Survey Volcano Hazards Program—Assess, forecast, prepare, engage

USGS Publications Warehouse

Stovall, Wendy K.; Wilkins, Aleeza M.; Mandeville, Charles W.; Driedger, Carolyn L.

2016-07-13

At least 170 volcanoes in 12 States and 2 territories have erupted in the past 12,000 years and have the potential to erupt again. Consequences of eruptions from U.S. volcanoes can extend far beyond the volcano’s immediate area. Many aspects of our daily life are vulnerable to volcano hazards, including air travel, regional power generation and transmission infrastructure, interstate transportation, port facilities, communications infrastructure, and public health. The U.S. Geological Survey has the Federal responsibility to issue timely warnings of potential volcanic activity to the affected populace and civil authorities. The Volcano Hazards Program (VHP) is funded to carry out that mission and does so through a combination of volcano monitoring, short-term warnings, research on how volcanoes work, and community education and outreach.

Field-trip guide to mafic volcanism of the Cascade Range in Central Oregon—A volcanic, tectonic, hydrologic, and geomorphic journey

USGS Publications Warehouse

Deligne, Natalia I.; Mckay, Daniele; Conrey, Richard M.; Grant, Gordon E.; Johnson, Emily R.; O'Connor, Jim; Sweeney, Kristin

2017-08-16

The Cascade Range in central Oregon has been shaped by tectonics, volcanism, and hydrology, as well as geomorphic forces that include glaciations. As a result of the rich interplay between these forces, mafic volcanism here can have surprising manifestations, which include relatively large tephra footprints and extensive lava flows, as well as water shortages, transportation and agricultural disruption, and forest fires. Although the focus of this multidisciplinary field trip will be on mafic volcanism, we will also look at the hydrology, geomorphology, and ecology of the area, and we will examine how these elements both influence and are influenced by mafic volcanism. We will see mafic volcanic rocks at the Sand Mountain volcanic field and in the Santiam Pass area, at McKenzie Pass, and in the southern Bend region. In addition, this field trip will occur during a total solar eclipse, the first one visible in the United States in more than 25 years (and the first seen in the conterminous United States in more than 37 years).The Cascade Range is the result of subduction of the Juan de Fuca plate underneath the North American plate. This north-south-trending volcanic mountain range is immediately downwind of the Pacific Ocean, a huge source of moisture. As moisture is blown eastward from the Pacific on prevailing winds, it encounters the Cascade Range in Oregon, and the resulting orographic lift and corresponding rain shadow is one of the strongest precipitation gradients in the conterminous United States. We will see how the products of the volcanoes in the central Oregon Cascades have had a profound influence on groundwater flow and, thus, on the distribution of Pacific moisture. We will also see the influence that mafic volcanism has had on landscape evolution, vegetation development, and general hydrology.

Eruptive history, current activity and risk estimation using geospatial information in the Colima volcano, Mexico

NASA Astrophysics Data System (ADS)

Suarez-Plascencia, C.; Camarena-Garcia, M.; Nunez-Cornu, F. J.; Flores-Peña, S.

2013-12-01

Colima volcano, also known as Volcan de Fuego (19 30.696 N, 103 37.026 W), is located on the border between the states of Jalisco and Colima, and is the most active volcano in Mexico. In January 20, 1913, Colima had its biggest explosion of the twentieth century, with VEI 4, after the volcano had been dormant for almost 40 years. In 1961, a dome reached the northeastern edge of the crater and started a new lava flow, and from this date maintains constant activity. In February 10, 1999, a new explosion occurred at the summit dome. The activity during the 2001-2005 period was the most intense, but did not exceed VEI 3. The activity resulted in the formation of domes and their destruction after explosive events. The explosions originated eruptive columns, reaching altitudes between 4,500 and 9,000 masl, further pyroclastic flows reaching distances up to 3.5 km from the crater. During the explosive events, ash emissions were generated in all directions reaching distances up to 100 km, slightly affecting the nearby villages: Tuxpan, Tonila, Zapotlan, Cuauhtemoc, Comala, Zapotitlan de Vadillo and Toliman. During 2005 to July 2013, this volcano has had an intense effusive-explosive activity; similar to the one that took place during the period of 1890 through 1905. That was before the Plinian eruption of 1913, where pyroclastic flows reached a distance of 15 km from the crater. In this paper we estimate the risk of Colima volcano through the analysis of the vulnerability variables, hazard and exposure, for which we use: satellite imagery, recurring Fenix helicopter over flights of the state government of Jalisco, the use of the images of Google Earth and the population census 2010 INEGI. With this information and data identified changes in economic activities, development, and use of land. The expansion of the agricultural frontier in the lower sides of the volcano Colima, and with the advancement of traditional crops of sugar cane and corn, increased the growth of avocado orchards and fruits like blueberries, raspberries, and blackberries within the radius of 15 km from the crater. The population dynamics in the Colima volcano area had a population of 552,954 inhabitants in 2010, and a growth at an annual rate of 1.6 percent of the total population. 60 percent of the populations live in 105 towns with a population less than 250 inhabitants. Also, the region showed an increase in vulnerability for the development of economic activities, supported by the highway, railway, natural gas pipelines and electrical infrastructure that connect to the Port of Manzanillo to Guadalajara city. With the use of geospatial information quantify the vulnerability, together with the hazard maps and exposure, enabled us to build the following volcanic risk maps: a) Exclusion areas and moderate hazard for explosive events (ballistic) and pyroclastic flows, b) Hazard map of lahars and debris flow, and c) Hazard map of ash-fall. The geospatial database, a GIS mapping and current volcano monitoring, are the basis of the Operational Plan Colima Volcano. Civil Protection by the state of Jalisco and the updating of urban development plans of municipalities converge on the volcano. These instruments of land planning will help reduce volcanic risk in the region.

Preliminary Study on Ground-Magnetic Data Near the Active Volcanoes in Konga Bay, East Flores Indonesia

NASA Astrophysics Data System (ADS)

Laesanpura, Agus; Dahrin, Darharta; Nurseptian, Ivan

2017-04-01

East Flores is part of Nusa Tenggara island belongs to volcanic arc zone, hence the active volcanoes surround the area about 60 × 50 square km. It is located at latitude south 8° 30’, and longitude east 122° 45’. Geologically, the rock is mostly of volcanic material since Miocene age. The Intriguing question is where the volcanic feeder, pyroclastic, and how it vanish in subsurface. The magnetic data acquisitions were executed on land for 500 meter interval and denser through the bay surrounded by volcanoes. The combine reduction to pole and forward modelling is apply for serve interpretation using forward modelling technique. The two interpretation sections, show the body of magmatic may present at depth about 2 to 3 km. The observation show no significant decreasing or loosening of magnetic anomaly although near the active volcano. We suggest the thermal anomaly is just disturbing magnetic data in near surface but not in the depth one. Meanwhile the reduction to pole’s section could distinguish the two group of rock. In assuming the layer is flat. The inferred peak of magmatic body near the existing volcano; and the active demagnetization associated through evidence of hot spring and inferred fault structure.

Uranium-Series Isotopic Constraints on Recent Changes in the Eruptive Behaviour of Merapi Volcano, Java, Indonesia

NASA Astrophysics Data System (ADS)

Gertisser, R.; Handley, H. K.; Reagan, M. K.; Berlo, K.; Barclay, J.; Preece, K.; Herd, R.

2011-12-01

Merapi volcano (Central Java) is one of the most active and deadly volcanoes in Indonesia. The 2010 eruption was the volcano's largest eruption since 1872 and erupted much more violently than expected. Prior to 2010, volcanic activity at Merapi was characterised by several months of slow dome growth punctuated by gravitational dome failures, generating small-volume pyroclastic density currents (Merapi-type nuées ardentes). The unforeseen, large-magnitude events in 2010 were different in many respects: pyroclastic density currents travelled > 15 km beyond the summit causing widespread devastation in proximal areas on Merapi's south flank and ash emissions from sustained eruption columns resulted in ash fall tens of kilometres away from the volcano. The 2010 events have proved that Merapi's relatively small dome-forming activity can be interrupted at relatively short notice by larger explosive eruptions, which appear more common in the geological record. We present new geochemical and Uranium-series isotope data for the volcanic products of both the 2006 and 2010 eruptions at Merapi to investigate the driving forces behind this unusual explosive behaviour and their timescales. An improved knowledge of these processes and of changes in the pre-eruptive magma system has important implications for the assessment of hazards and risks from future eruptive activity at Merapi.

Long-term eruptive activity at a submarine arc volcano

USGS Publications Warehouse

Embley, R.W.; Chadwick, W.W.; Baker, E.T.; Butterfield, D.A.; Resing, J.A.; de Ronde, Cornel E. J.; Tunnicliffe, V.; Lupton, J.E.; Juniper, S.K.; Rubin, K.H.; Stern, R.J.; Lebon, G.T.; Nakamura, K.-I.; Merle, S.G.; Hein, J.R.; Wiens, D.A.; Tamura, Y.

2006-01-01

Three-quarters of the Earth's volcanic activity is submarine, located mostly along the mid-ocean ridges, with the remainder along intraoceanic arcs and hotspots at depths varying from greater than 4,000 m to near the sea surface. Most observations and sampling of submarine eruptions have been indirect, made from surface vessels or made after the fact. We describe here direct observations and sampling of an eruption at a submarine arc volcano named NW Rota-1, located 60 km northwest of the island of Rota (Commonwealth of the Northern Mariana Islands). We observed a pulsating plume permeated with droplets of molten sulphur disgorging volcanic ash and lapilli from a 15-m diameter pit in March 2004 and again in October 2005 near the summit of the volcano at a water depth of 555 m (depth in 2004). A turbid layer found on the flanks of the volcano (in 2004) at depths from 700 m to more than 1,400 m was probably formed by mass-wasting events related to the eruption. Long-term eruptive activity has produced an unusual chemical environment and a very unstable benthic habitat exploited by only a few mobile decapod species. Such conditions are perhaps distinctive of active arc and hotspot volcanoes. ?? 2006 Nature Publishing Group.

Analysis of active volcanoes from the Earth Observing System

NASA Technical Reports Server (NTRS)

Mouginis-Mark, Peter; Rowland, Scott; Crisp, Joy; Glaze, Lori; Jones, Kenneth; Kahle, Anne; Pieri, David; Zebker, Howard; Krueger, Arlin; Walter, Lou

1991-01-01

The Earth Observing System (EOS) scheduled for launch in 1997 and 1999 is briefly described, and the EOS volcanology investigation objectives are discussed. The volcanology investigation will include long- and short-term monitoring of selected volcanoes, the detection of precursor activity associated with unanticipated eruptions, and a detailed study of on-going eruptions. A variety of instruments on the EOS platforms will enable the study of local- and regional-scale thermal and deformational features of volcanoes, and the chemical and structural features of volcanic eruption plumes and aerosols.

Earth observations taken during STS-83 mission

NASA Image and Video Library

2016-08-12

STS083-747-088 (4-8 April 1997)--- Mayon Volcano with a Plume, Luzon, the Philippines Mayon has the classic conical shape of a strato volcano. It is the most active volcano in the Philippines and continues to be active as demonstrated by the plume in the photo. Since 1616, Mayon has erupted 47 times. The most recent major eruption, in 1993, began unexpectedly with an explosion. The initial eruption lasted only 30 minutes but it generated pyroclastic flows that killed 68 people and prompted the evacuation of 60,000 others.

Output rate of magma from active central volcanoes

NASA Technical Reports Server (NTRS)

Wadge, G.

1980-01-01

For part of their historic records, nine of the most active volcanoes on earth have each erupted magma at a nearly constant rate. These output rates are very similar and range from 0.69 to 0.26 cu m/s. The volcanoes discussed - Kilauea, Mauna Loa, Fuego, Santiaguito, Nyamuragira, Hekla, Piton de la Fournaise, Vesuvius and Etna - represent almost the whole spectrum of plate tectonic settings of volcanism. A common mechanism of buoyantly rising magma-filled cracks in the upper crust may contribute to the observed restricted range of the rates of output.

Earth observations taken by the Expedition Seven crew

NASA Image and Video Library

2003-08-24

ISS007-E-13327 (24 August 2003) --- This view featuring Java’s Merapi volcano was photographed by one of the Expedition 7 crewmembers onboard the International Space Station (ISS). At 2,911 meters, the summit of Merapi and its vigorous steam plume rises above a bank of stratus clouds. One of Indonesia’s most active volcanoes, it has been almost continuously active for nearly ten years, including periodic pyroclastic flows and avalanches. The volcano is located less than 25 miles north of the city of Yogykarta in central Java.

Earth Observation taken by the Expedition 19 crew

NASA Image and Video Library

2009-04-28

ISS019-E-011922 (28 April 2009) --- Mauna Kea Volcano in Hawaii is featured in this image photographed by an Expedition 19 crewmember on the International Space Station. The island of Hawaii is home to four volcanoes monitored by volcanologists ? Mauna Loa, Hualalai, Kilauea, and Mauna Kea. Mauna Kea is depicted in this view; of the four volcanoes, it is the only one that has not erupted during historical times. The Hawaiian Islands chain, together with the submerged Emperor Chain to the northwest, form an extended line of volcanic islands and seamounts that is thought to record passage of the Pacific Plate over a ?hotspot? (or thermal plume) in the Earth?s mantle. Areas of active volcanism in the southern Hawaiian Islands today mark the general location of the hotspot. This detailed photograph illustrates why the volcano is called Mauna Kea (?white mountain? in Hawaiian). While the neighboring Mauna Loa volcano is a classic shield volcano comprised of dark basaltic lava flows, Mauna Kea experienced more explosive activity during its last eruptive phase. This covered its basalt lava flows with pyroclastic deposits that are visible as the light brown area surrounding snow on the summit (center). Numerous small red to dark gray cinder cones are another distinctive feature of Mauna Loa. The cinder cones represent the most recent type of volcanic activity at the volcano. A small area of buildings and roadways at upper right is the Pohakuloa Training Area. This is the largest US Department of Defense facility in the state of Hawaii. The site is used for U.S. Army and Marine Corps exercises.

Linear models of activation cascades: analytical solutions and coarse-graining of delayed signal transduction

PubMed Central

Desikan, Radhika

2016-01-01

Cellular signal transduction usually involves activation cascades, the sequential activation of a series of proteins following the reception of an input signal. Here, we study the classic model of weakly activated cascades and obtain analytical solutions for a variety of inputs. We show that in the special but important case of optimal gain cascades (i.e. when the deactivation rates are identical) the downstream output of the cascade can be represented exactly as a lumped nonlinear module containing an incomplete gamma function with real parameters that depend on the rates and length of the cascade, as well as parameters of the input signal. The expressions obtained can be applied to the non-identical case when the deactivation rates are random to capture the variability in the cascade outputs. We also show that cascades can be rearranged so that blocks with similar rates can be lumped and represented through our nonlinear modules. Our results can be used both to represent cascades in computational models of differential equations and to fit data efficiently, by reducing the number of equations and parameters involved. In particular, the length of the cascade appears as a real-valued parameter and can thus be fitted in the same manner as Hill coefficients. Finally, we show how the obtained nonlinear modules can be used instead of delay differential equations to model delays in signal transduction. PMID:27581482

Earth observations taken by Expedition 38 crewmember

NASA Image and Video Library

2013-12-06

ISS038-E-012569 (6 Dec. 2013) --- Sollipulli Caldera is featured in this image photographed by an Expedition 38 crew member on the International Space Station. While active volcanoes are obvious targets of interest from the standpoint of natural hazards, there are some dormant volcanoes that nevertheless warrant concern due to their geologic history of activity. One such volcano is Sollipulli, located in central Chile near the border with Argentina in the southern Andes Mountains of South America. The volcano is located within the Parque Nacional Villarica of Chile. This photograph highlights the summit (2,282 meters above sea level) of the volcano and the bare slopes above the tree line. Lower elevations are covered with the green forests indicative of Southern Hemisphere summer. The summit of the volcano is occupied by a four-kilometer-wide caldera, currently filled with a snow-covered glacier (center). While most calderas form following violent explosive eruptions, the types of volcanic rock and deposits associated with such an event have not been found at Sollipulli. The geologic evidence does indicate explosive activity 2,900 years before present, and production of lava flows approximately 700 years before present. Together with craters and scoria cones located along the outer flanks of the caldera, scientists say this history suggests that Sollipulli could experience violent eruptions again, presenting an immediate potential hazard to such towns as Melipeuco in addition to the greater region.

Establishment, test and evaluation of a prototype volcano surveillance system

NASA Technical Reports Server (NTRS)

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

1973-01-01

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

Collaborative Monitoring and Hazard Mitigation at Fuego Volcano, Guatemala

NASA Astrophysics Data System (ADS)

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

2007-05-01

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

Preliminary volcano-hazard assessment for Kanaga Volcano, Alaska

USGS Publications Warehouse

Waythomas, Christopher F.; Miller, Thomas P.; Nye, Christopher J.

2002-01-01

Kanaga Volcano is a steep-sided, symmetrical, cone-shaped, 1307 meter high, andesitic stratovolcano on the north end of Kanaga Island (51°55’ N latitude, 177°10’ W longitude) in the western Aleutian Islands of Alaska. Kanaga Island is an elongated, low-relief (except for the volcano) island, located about 35 kilometers west of the community of Adak on Adak Island and is part of the Andreanof Islands Group of islands. Kanaga Volcano is one of the 41 historically active volcanoes in Alaska and has erupted numerous times in the past 11,000 years, including at least 10 eruptions in the past 250 years (Miller and others, 1998). The most recent eruption occurred in 1993-95 and caused minor ash fall on Adak Island and produced blocky aa lava flows that reached the sea on the northwest and west sides of the volcano (Neal and others, 1995). The summit of the volcano is characterized by a small, circular crater about 200 meters in diameter and 50-70 meters deep. Several active fumaroles are present in the crater and around the crater rim. The flanking slopes of the volcano are steep (20-30 degrees) and consist mainly of blocky, linear to spoonshaped lava flows that formed during eruptions of late Holocene age (about the past 3,000 years). The modern cone sits within a circular caldera structure that formed by large-scale collapse of a preexisting volcano. Evidence for eruptions of this preexisting volcano mainly consists of lava flows exposed along Kanaton Ridge, indicating that this former volcanic center was predominantly effusive in character. In winter (October-April), Kanaga Volcano may be covered by substantial amounts of snow that would be a source of water for lahars (volcanic mudflows). In summer, much of the snowpack melts, leaving only a patchy distribution of snow on the volcano. Glacier ice is not present on the volcano or on other parts of Kanaga Island. Kanaga Island is uninhabited and is part of the Alaska Maritime National Wildlife Refuge, managed by the U.S. Fish and Wildlife Service. The island is remote and often shrouded by clouds and fog. It can be reached only by boat, helicopter,or amphibiouslanding aircraft.

Publications - DDS 6 | Alaska Division of Geological & Geophysical Surveys

Science.gov Websites

Publications Geologic Materials Center General Information Inventory Monthly Report Hours and Location Policy DGGS DDS 6 Publication Details Title: Historically active volcanoes of Alaska Authors: Cameron, C.E , C.E., and Schaefer, J.R., 2016, Historically active volcanoes of Alaska: Alaska Division of Geological

Iridium emissions from Hawaiian volcanoes

NASA Technical Reports Server (NTRS)

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

1988-01-01

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

Volcano-tectonic implications of 3-D velocity structures derived from joint active and passive source tomography of the island of Hawaii

USGS Publications Warehouse

Park, J.; Morgan, J.K.; Zelt, C.A.; Okubo, P.G.

2009-01-01

We present a velocity model of the onshore and offshore regions around the southern part of the island of Hawaii, including southern Mauna Kea, southeastern Hualalai, and the active volcanoes of Mauna Loa, and Kilauea, and Loihi seamount. The velocity model was inverted from about 200,000 first-arrival traveltime picks of earthquakes and air gun shots recorded at the Hawaiian Volcano Observatory (HVO). Reconstructed volcanic structures of the island provide us with an improved understanding of the volcano-tectonic evolution of Hawaiian volcanoes and their interactions. The summits and upper rift zones of the active volcanoes are characterized by high-velocity materials, correlated with intrusive magma cumulates. These high-velocity materials often do not extend the full lengths of the rift zones, suggesting that rift zone intrusions may be spatially limited. Seismicity tends to be localized seaward of the most active intrusive bodies. Low-velocity materials beneath parts of the active rift zones of Kilauea and Mauna Loa suggest discontinuous rift zone intrusives, possibly due to the presence of a preexisting volcanic edifice, e.g., along Mauna Loa beneath Kilauea's southwest rift zone, or alternatively, removal of high-velocity materials by large-scale landsliding, e.g., along Mauna Loa's western flank. Both locations also show increased seismicity that may result from edifice interactions or reactivation of buried faults. New high-velocity regions are recognized and suggest the presence of buried, and in some cases, previously unknown rift zones, within the northwest flank of Mauna Loa, and the south flanks of Mauna Loa, Hualalai, and Mauna Kea. Copyright 2009 by the American Geophysical Union.

Volcano-hazard zonation for San Vicente volcano, El Salvador

USGS Publications Warehouse

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

2001-01-01

San Vicente volcano, also known as Chichontepec, is one of many volcanoes along the volcanic arc in El Salvador. This composite volcano, located about 50 kilometers east of the capital city San Salvador, has a volume of about 130 cubic kilometers, rises to an altitude of about 2180 meters, and towers above major communities such as San Vicente, Tepetitan, Guadalupe, Zacatecoluca, and Tecoluca. In addition to the larger communities that surround the volcano, several smaller communities and coffee plantations are located on or around the flanks of the volcano, and major transportation routes are located near the lowermost southern and eastern flanks of the volcano. The population density and proximity around San Vicente volcano, as well as the proximity of major transportation routes, increase the risk that even small landslides or eruptions, likely to occur again, can have serious societal consequences. The eruptive history of San Vicente volcano is not well known, and there is no definitive record of historical eruptive activity. The last significant eruption occurred more than 1700 years ago, and perhaps long before permanent human habitation of the area. Nevertheless, this volcano has a very long history of repeated, and sometimes violent, eruptions, and at least once a large section of the volcano collapsed in a massive landslide. The oldest rocks associated with a volcanic center at San Vicente are more than 2 million years old. The volcano is composed of remnants of multiple eruptive centers that have migrated roughly eastward with time. Future eruptions of this volcano will pose substantial risk to surrounding communities.

Erupting Volcano Mount Etna

NASA Technical Reports Server (NTRS)

2002-01-01

Expedition Five crew members aboard the International Space Station (ISS) captured this overhead look at the smoke and ash regurgitated from the erupting volcano Mt. Etna on the island of Sicily, Italy in October 2002. Triggered by a series of earthquakes on October 27, 2002, this eruption was one of Etna's most vigorous in years. This image shows the ash plume curving out toward the horizon. The lighter-colored plumes down slope and north of the summit seen in this frame are produced by forest fires set by flowing lava. At an elevation of 10,990 feet (3,350 m), the summit of the Mt. Etna volcano, one of the most active and most studied volcanoes in the world, has been active for a half-million years and has erupted hundreds of times in recorded history.

Linking petrology and seismology at an active volcano.

PubMed

Saunders, Kate; Blundy, Jon; Dohmen, Ralf; Cashman, Kathy

2012-05-25

Many active volcanoes exhibit changes in seismicity, ground deformation, and gas emissions, which in some instances arise from magma movement in the crust before eruption. An enduring challenge in volcano monitoring is interpreting signs of unrest in terms of the causal subterranean magmatic processes. We examined over 300 zoned orthopyroxene crystals from the 1980-1986 eruption of Mount St. Helens that record pulsatory intrusions of new magma and volatiles into an existing larger reservoir before the eruption occurred. Diffusion chronometry applied to orthopyroxene crystal rims shows that episodes of magma intrusion correlate temporally with recorded seismicity, providing evidence that some seismic events are related to magma intrusion. These time scales are commensurate with monitoring signals at restless volcanoes, thus improving our ability to forecast volcanic eruptions by using petrology.

Evidence for a seismic activity mainly constituted of hybrid events at Cayambe volcano, Ecuador. Interpretation in a iced-domes volcano context

NASA Astrophysics Data System (ADS)

Guillier, Bertrand; Chatelain, Jean-Luc

2006-06-01

The high activity level of Hybrid Events (HE) detected beneath the Cayambe volcano since 1989 has been more thoroughly investigated with data from a temporary array. The unusual HE spectral content allows separating a high-frequency signal riding on a low-frequency one, with a probable single source. HEs are interpreted as high frequency VT events, produced by the interaction between magmatic heat and an underground water system fed by thaw water from the summital glacier, which trigger simultaneous low-frequency fluid resonance in the highly fractured adjacent medium. Pure VTs are interpreted as 'aborted' HEs occurring probably in the oldest and coldest part of the volcano complex. To cite this article: B. Guillier, J.-L. Chatelain, C. R. Geoscience 338 (2006).

Klyuchevskaya Volcano

NASA Technical Reports Server (NTRS)

2007-01-01

The Klyuchevskaya Volcano on Russia's Kamchatka Peninsula continued its ongoing activity by releasing another plume on May 24, 2007. The same day, the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Terra satellite captured this image, at 01:00 UTC. In this image, a hotspot marks the volcano's summit. Outlined in red, the hotspot indicates where MODIS detected unusually warm surface temperatures. Blowing southward from the summit is the plume, which casts its shadow on the clouds below. Near the summit, the plume appears gray, and it lightens toward the south. With an altitude of 4,835 meters (15,863 feet), Klyuchevskaya (sometimes spelled Klyuchevskoy or Kliuchevskoi) is both the highest and most active volcano on the Kamchatka Peninsula. As part of the Pacific 'Ring of Fire,' the peninsula experiences regular seismic activity as the Pacific Plate slides below other tectonic plates in the Earth's crust. Klyuchevskaya is estimated to have experienced more than 100 flank eruptions in the past 3,000 years. Since its formation 6,000 years ago, the volcano has seen few periods of inactivity. NASA image courtesy the MODIS Rapid Response Team at NASA GSFC. The Rapid Response Team provides daily images of this region.

On the carcinogenic polycyclic aromatic hydrocarbon benzo(a)pyrene in volcano exhausts.

PubMed

Ilnitsky, A P; Belitsky, G A; Shabad, L M

1976-05-01

The content of benzo(a)pyrene in the juvenile ashes of the volcano Tyatya (Kunashir Island, Kuriles) and in the soil, vegetation and volcanic mud collected near volcanos in Kamchatka was studied. It was concluded that volcanic activity does not play a large role in forming the background level of this carcinogen in the human environment.

Incorporating Community Knowledge to Lahar Hazard Maps: Canton Buenos Aires Case Study, at Santa Ana (Ilamatepec) Volcano

NASA Astrophysics Data System (ADS)

Bajo, J. V.; Martinez-Hackert, B.; Polio, C.; Gutierrez, E.

2015-12-01

Santa Ana (Ilamatepec) Volcano is an active composite volcano located in the Apaneca Volcanic Field located in western part of El Salvador, Central America. The volcano is surrounded by rural communities in its proximal areas and the second (Santa Ana, 13 km) and fourth (Sonsosante, 15 km) largest cities of the country. On October 1st, 2005, the volcano erupted after months of increased activity. Following the eruption, volcanic mitigation projects were conducted in the region, but the communities had little or no input on them. This project consisted in the creation of lahar volcanic hazard map for the Canton Buanos Aires on the northern part of the volcano by incorporating the community's knowledge from prior events to model parameters and results. The work with the community consisted in several meetings where the community members recounted past events. They were asked to map the outcomes of those events using either a topographic map of the area, a Google Earth image, or a blank paper poster size. These maps have been used to identify hazard and vulnerable areas, and for model validation. These maps were presented to the communities and they accepted their results and the maps.

Relocating San Miguel Volcanic Seismic Events for Receiver Functions and Tomographic Models

NASA Astrophysics Data System (ADS)

Patlan, E.; Velasco, A. A.; Konter, J.

2009-12-01

The San Miguel volcano lies near the city of San Miguel, El Salvador (13.43N and -88.26W). San Miguel volcano, an active stratovolcano, presents a significant natural hazard for the city of San Miguel. Furthermore, the internal state and activity of volcanoes remains an important component to understanding volcanic hazard. The main technology for addressing volcanic hazards and processes is through the analysis of data collected from the deployment of seismic sensors that record ground motion. Six UTEP seismic stations were deployed around San Miguel volcano from 2007-2008 to define the magma chamber and assess the seismic and volcanic hazard. We utilize these data to develop images of the earth structure beneath the volcano, studying the volcanic processes by identifying different sources, and investigating the role of earthquakes and faults in controlling the volcanic processes. We will calculate receiver functions to determine the thickness of San Miguel volcano internal structure, within the Caribbean plate. Crustal thicknesses will be modeled using calculated receiver functions from both theoretical and hand-picked P-wave arrivals. We will use this information derived from receiver functions, along with P-wave delay times, to map the location of the magma chamber.

Recent unrest and magma movements at Eyjafjallajökull and Katla volcanoes, Iceland

NASA Astrophysics Data System (ADS)

Sturkell, Erik; Sigmundsson, Freysteinn; Einarsson, PáLl

2003-08-01

Katla and Eyjafjallajökull volcanoes are situated 25 km apart at the southern tip of the Eastern Volcanic Zone in Iceland. Both have been active in historic time (last 1100 years) and have a history of simultaneous activity. The much more active Katla volcano has erupted at least 20 times, and Eyjafjallajökull's two eruptions were contemporaneous with Katla eruptions. Following a quiet period of several decades, the seismicity beneath Eyjafjallajökull was high in 1994 and again in 1999. The activity culminated in July 1999 when a flash flood occurred from the Mýrdalsjökull ice cap covering Katla, associated with changes in seismicity, bursts of volcanic tremor, and the formation and deepening of ice cauldrons. We report here results of deformation observations of these events, both by GPS geodesy and tilt measurements. The 1999 increase in seismicity at Eyjafjallajökull was associated with significant inflation of the volcano. The deformation data are modeled by a point pressure source at 3.5 km depth beneath the flank of the volcano, about 4 km south of the summit crater. Maximum uplift of the model is 0.35 m. A similar model also explains deformation associated with the 1994 seismic crisis. The deformation field of the Katla volcano is more difficult to ascertain due to the extensive glacier coverage. Movements of points on nunataks on and near the caldera rim indicate inflation and magma movements at shallow level beneath the caldera in connection with the events of July 1999.

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

NASA Astrophysics Data System (ADS)

Neri, Marco; Neri, Emilia

2015-04-01

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

Long-lived structural control of Mt. Shasta's plumbing system illuminated by 40Ar/39Ar geochronology

NASA Astrophysics Data System (ADS)

Calvert, A. T.; Christiansen, R. L.

2013-12-01

Mt. Shasta is the largest stratovolcano in the Cascade Arc, surpassed in volume only by the large rear-arc Medicine Lake and Newberry composite volcanoes. Including the material in the ~350 ka debris avalanche, it has produced more than 500 km3 of andesite and dacite from several superimposed central vents over its 700-850 kyr history. Earlier, between at least 970 to 1170 ka, the Rainbow Mountain volcano of similar composition and size occupied this latitude of the arc ~20 km further east. This shift of magmatic focus from within the arc axis (as defined by 6 Ma and younger calc-alkaline centers) to the arc front is poorly understood, but the current center's location appears structurally controlled. Most identifiable volcanic vents on Mt. Shasta lie within 1 km of a N-S line through the active summit cone. 40Ar/39Ar ages of map units occupying the vent alignment range from the Holocene (5×1 ka) current summit dome to at least the Middle Pleistocene (464×9 ka McKenzie Butte). The vast majority of eruptions have issued from central vents (Sargents Ridge, 300-135 ka; Misery Hill, 100-15 ka; and Hotlum, <10 ka), each 500 to 1000m north of its predecessor. A central vent for the pre-avalanche edifice is impossible to locate precisely, but was possibly on the same N-S trend and certainly no more than 4 km to the west, likely south of the Sargents Ridge central vent. ~15 of ~25 mapped flank vents lie on the alignment and the other ten lie west of the line. No identified volcanic vents lie east of the line until >12 km from Mt. Shasta (Ash Creek Butte, 227 ka; Basalt of McCloud River, 38 ka; The Whaleback, 102 ka), and monogenetic and polygenetic centers further east and northeast. From these observations we infer that: (1) magmas are localized along a ~20 km, long-lived, N-S trending structure running through the summit; (2) the upper crustal structure appears impermeable to magmas and resistant to dikes on its eastern side; (3) the western half of the area beneath the volcano appears substantially weaker, as dikes have fed flank vents 10-20 km from the summit over the history of the volcano; and (4) the orientation of the WNW-directed debris avalanche, coincident with the greatest concentration of flank vents, may indicate either structural weakness or failure following emplacement of a cryptodome similar to the 1980 events at Mt. St. Helens.

Hazard maps of Colima volcano, Mexico

NASA Astrophysics Data System (ADS)

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

2011-12-01

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

Mount Cameroon

NASA Image and Video Library

2014-10-09

NASA Terra spacecraft shows Mount Cameroon, an active volcano in Cameroon near the Gulf of Guinea. It is one of Africa largest volcanoes, rising over 4,000 meters, with more than 100 small cinder cones.

Numerical simulation of tsunami generation by cold volcanic mass flows at Augustine Volcano, Alaska

USGS Publications Warehouse

Waythomas, C.F.; Watts, P.; Walder, J.S.

2006-01-01

Many of the world's active volcanoes are situated on or near coastlines. During eruptions, diverse geophysical mass flows, including pyroclastic flows, debris avalanches, and lahars, can deliver large volumes of unconsolidated debris to the ocean in a short period of time and thereby generate tsunamis. Deposits of both hot and cold volcanic mass flows produced by eruptions of Aleutian arc volcanoes are exposed at many locations along the coastlines of the Bering Sea, North Pacific Ocean, and Cook Inlet, indicating that the flows entered the sea and in some cases may have initiated tsunamis. We evaluate the process of tsunami generation by cold granular subaerial volcanic mass flows using examples from Augustine Volcano in southern Cook Inlet. Augustine Volcano is the most historically active volcano in the Cook Inlet region, and future eruptions, should they lead to debris-avalanche formation and tsunami generation, could be hazardous to some coastal areas. Geological investigations at Augustine Volcano suggest that as many as 12-14 debris avalanches have reached the sea in the last 2000 years, and a debris avalanche emplaced during an A.D. 1883 eruption may have initiated a tsunami that was observed about 80 km east of the volcano at the village of English Bay (Nanwalek) on the coast of the southern Kenai Peninsula. Numerical simulation of mass-flow motion, tsunami generation, propagation, and inundation for Augustine Volcano indicate only modest wave generation by volcanic mass flows and localized wave effects. However, for east-directed mass flows entering Cook Inlet, tsunamis are capable of reaching the more populated coastlines of the southwestern Kenai Peninsula, where maximum water amplitudes of several meters are possible.

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

USGS Publications Warehouse

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

2014-01-01

Large Hawaiian volcanoes can persist as islands through the rapid subsidence by building upward rapidly enough. But in the long run, subsidence, coupled with surface erosion, erases any volcanic remnant above sea level in about 15 m.y. One consequence of subsidence, in concert with eustatic changes in sea level, is the drowning of coral reefs that drape the submarine flanks of the actively subsiding volcanoes. At least six reefs northwest of the Island of Hawai‘i form a stairstep configuration, the oldest being deepest.

Volcano monitoring at the U.S. Geological Survey's Hawaiian Volcano Observatory

USGS Publications Warehouse

1986-01-01

The island of Hawaii has one of the youngest landscapes on Earth, formed by the frequent addition of new lava to its surface. Because Hawaiian eruptions are generally nonexplosive and easily accessible, the island has long attracted geologists interested in studying the extraordinary power of volcanic eruption. The U.S. Geological Survey's Hawaiian Volcano Observatory (HVO), now nearing its 75th anniversary, has been in the forefront of volcanology since the early 1900s. This issue of Earthquakes and Volcanoes is devoted to the work of the Observatory and its role in studying the most recent eruptions of Hawaii's two currently active volcanoes, Kilauea and Mauna Loa.

Volcano-Hydrothermal Systems of the Kuril Island Arc (Russia): Geochemistry of the Thermal Waters and Gases.

NASA Astrophysics Data System (ADS)

Kalacheva, E.; Taran, Y.; Voloshina, E.; Kotenko, T.; Tarasov, K.

2017-12-01

More than 30 active volcanoes with historical eruptions are known on 20 main islands composing the Kuril Arc. Eight islands - Paramushir, Shiashkotan, Rasshua, Ushishir, Ketoy, Urup, Iturup and Kunashir - are characterized by hydrothermal activity, complementary to the fumarole activity in the craters and volcano slopes. At Paramushir, Shiashkotan, Iturup and Kunashir most of thermal manifestations are acidic to ultra-acidic hot springs associated with hydrothermal aquifers inside volcano edifices. The most powerful of them is the ultra-acid hydrothermal system of Ebeko volcano (Paramushir island) with more than 80 t/day of the chloride output and pH of springs of 1.5. At the summit part of the Ebeko volcano there are 12 thermal fields with the total thermal area exceeding 1 km2. The measured temperatures of fumaroles are from 98º C to 500ºC. Another type of hydrothermal activity are the wide spread coastal hot and neutral springs situated as a rule within the tide zone. Four groups of this type of thermal manifestation were found on the western shore of Shiashkotan island. It have Na-Ca-Cl-SO4 composition with temperatures 50-80°C and TDS 7-8 g/L. Coastal neutral springs were found also on Russhua, Uturup and Kunashir islands. Ushishir volcano-hydrothermal system in the middle of the arc is formed by the absorption of magmatic gases by seawater. In the crater of the Pallas cone (Ketoy island) there is a small Glazok lake with acid SO4 water and pH=2.4, TDS=2g/L, T=12oC. Ketoy volcano on the same island hosts a high temperature hydrothermal system with unusual boiling Ca-Na-SO4 neutral springs and steam vents. Mendeleev and Golovnin volcanoes on Kunashir Island are the southernmost of the Kuril arc. Mendeleev edifice is a centre of a large thermal area with many manifestations of different types including steam vents, acid springs and neutral coastal springs. In a 4.2x4 km wide caldera of Golovnin volcano there are two lakes with acid Cl-SO4 water and numerous thermal vents around and on the bottom of the lakes and outside the caldera, along the coast of the Sea of Okhotsk. In this report we present new data on the chemical (major and trace elements) and isotopic (H, O) composition of thermal fluids and gases from thermal manifestations obtained during the field campaign in 2015-2017. This work is supported by the RSF grant #15-17-20011.

A cascading activity-based probe sequentially targets E1–E2–E3 ubiquitin enzymes

PubMed Central

Mulder, Monique P.C.; Witting, Katharina; Berlin, Ilana; Pruneda, Jonathan N.; Wu, Kuen-Phon; Chang, Jer-Gung; Merkx, Remco; Bialas, Johanna; Groettrup, Marcus; Vertegaal, Alfred C.O.; Schulman, Brenda A.; Komander, David; Neefjes, Jacques; Oualid, Farid El; Ovaa, Huib

2016-01-01

Post-translational modifications of proteins with ubiquitin (Ub) and ubiquitin-like (Ubl) modifiers, orchestrated by a cascade of specialized E1, E2 and E3 enzymes, control a staggering breadth of cellular processes. To monitor catalysis along these complex reaction pathways, we developed a cascading activity-based probe, UbDha. Akin to the native Ub, upon ATP-dependent activation by the E1, UbDha can travel downstream to the E2 (and subsequently E3) enzymes through sequential trans-thioesterifications. Unlike the native Ub, at each step along the cascade UbDha has the option to react irreversibly with active site cysteine residues of target enzymes, thus enabling their detection. We show that our cascading probe ‘hops’ and ‘traps’ catalytically active ubiquitin-modifying enzymes (but not their substrates) by a mechanism diversifiable to Ubls. Our founder methodology, amenable to structural studies, proteome-wide profiling and monitoring of enzymatic activities in living cells, presents novel and versatile tools to interrogate the Ub/Ubl cascades. PMID:27182664

Long-term changes in explosive and effusive behaviour at andesitic arc volcanoes: Chronostratigraphy of the Centre Hills Volcano, Montserrat

NASA Astrophysics Data System (ADS)

Coussens, Maya; Cassidy, Michael; Watt, Sebastian F. L.; Jutzeler, Martin; Talling, Peter J.; Barfod, Dan; Gernon, Thomas M.; Taylor, Rex; Hatter, Stuart J.; Palmer, Martin R.; Montserrat Volcano Observatory

2017-03-01

Volcanism on Montserrat (Lesser Antilles arc) has migrated southwards since the formation of the Silver Hills 2.5 Ma, and has formed three successively active volcanic centres. The Centre Hills volcano was the focus of volcanism from 1-0.4 Ma, before activity commenced at the currently active Soufrière Hills volcano. The history of activity at these two volcanoes provides an opportunity to investigate the pattern of volcano behaviour on an andesitic arc island over the lifetime of individual volcanoes. Here, we describe the pyroclastic stratigraphy of subaerial exposures around central Montserrat; identifying 11 thick (> 1 m) pumiceous units derived from sustained explosive eruptions of Centre Hills from 0.8-0.4 Ma. Over 10 other, less well- exposed pumiceous units have also been identified. The pumice-rich units are interbedded with andesite lava breccias derived from effusive, dome-forming eruptions of Centre Hills. The stratigraphy indicates that large (up to magnitude 5) explosive eruptions occurred throughout the history of Centre Hills, alongside effusive activity. This behaviour at Centre Hills contrasts with Soufrière Hills, where deposits from sustained explosive eruptions are much less common and restricted to early stages of activity at the volcano, from 175-130 ka. Subsequent eruptions at Soufriere Hills have been dominated by andesitic effusive eruptions. The bulk composition, petrography and mineral chemistry of volcanic rocks from Centre Hills and Soufrière Hills are similar throughout the history of both volcanoes, except for occasional, transient departures to different magma compositions, which mark shifts in vent location or dominant eruption style. For example, the final recorded eruption of Centre Hills, before the initiation of activity at Soufrière Hills, was more silicic than any other identified eruption on Montserrat; and the basaltic South Soufrière Hills episode marked the transition to the current stage of predominantly effusive Soufrière Hills activity. The compositional stability observed throughout the history of Centre Hills and Soufrière Hills suggests that a predominance towards effusive or explosive eruption styles is not driven by major compositional shifts of magma, but may reflect local changes in long-term magma storage conditions that characterise individual episodes (on 105 year timescales) of volcanism on Montserrat. Supplementary Table 2: Complete XRF analyses for all analysed samples Supplementary Table 3: Complete ICP-MS analyses for all analysed samples. Supplementary Table 4: Plagioclase composition and precision data from SEM analysis Supplementary Table 5: Clinopyroxene composition and precision data from SEM analysis Supplementary Table 6: Orthopyroxene composition and precision data from SEM analysis Supplementary Table 7: Amphibole composition and precision data from SEM analysis Supplementary Table 8: Glass compositions from EMP analysis Supplementary Table 9: Standard Deviation of glass compositions from EMP analysis. Supplementary Table 10: Isotopic composition of argon from plagioclase crystals from select units. Data obtained using an ARGUS V multi-collector mass spectrometer.

The spectrum of persistent volcanic flank instability: A review and proposed framework based on Kīlauea, Piton de la Fournaise, and Etna

NASA Astrophysics Data System (ADS)

Poland, Michael P.; Peltier, Aline; Bonforte, Alessandro; Puglisi, Giuseppe

2017-06-01

Persistent motion of the south flank of Kīlauea Volcano, Hawai'i, has been known for several decades, but has only recently been identified at other large basaltic volcanoes-namely Piton de la Fournaise (La Réunion) and Etna (Sicily)-thanks to the advent of space geodetic techniques. Nevertheless, understanding of long-term flank instability is based largely on the example of Kīlauea, despite the large differences in the manifestations and mechanisms of the process when viewed through a comparative lens. For example, the rate of flank motion at Kīlauea is several times that of Etna and Piton de la Fournaise and is accommodated on a slip plane several km deeper than is probably present at the other two volcanoes. Gravitational spreading also appears to be the dominant driving force at Kīlauea, given the long-term steady motion of the volcano's south flank regardless of eruptive/intrusive activity, whereas magmatic activity plays a larger role in flank deformation at Etna and Piton de la Fournaise. Kīlauea and Etna, however, are both characterized by heavily faulted flanks, while Piton de la Fournaise shows little evidence for flank faulting. A helpful means of understanding the spectrum of persistent flank motion at large basaltic edifices may be through a framework defined on one hand by magmatic activity (which encompasses both magma supply and edifice size), and on the other hand by the structural setting of the volcano (especially the characteristics of the subvolcanic basement or subhorizontal intravolcanic weak zones). A volcano's size and magmatic activity will dictate the extent to which gravitational and magmatic forces can drive motion of an unstable flank (and possibly the level of faulting of that flank), while the volcano's structural setting governs whether or not a plane of weakness exists beneath or within the edifice and can facilitate flank slip. Considering persistent flank instability using this conceptual model is an alternative to using a single volcano as a "type example"-especially given that the example is usually Kīlauea, which defines an extreme end of the spectrum-and can provide a basis for understanding why flank motion may or may not exist on other large basaltic volcanoes worldwide.

Distribution of melt beneath Mount St Helens and Mount Adams inferred from magnetotelluric data

NASA Astrophysics Data System (ADS)

Hill, Graham J.; Caldwell, T. Grant; Heise, Wiebke; Chertkoff, Darren G.; Bibby, Hugh M.; Burgess, Matt K.; Cull, James P.; Cas, Ray A. F.

2009-11-01

Three prominent volcanoes that form part of the Cascade mountain range in Washington State (USA)-Mounts St Helens, Adams and Rainier-are located on the margins of a mid-crustal zone of high electrical conductivity. Interconnected melt can increase the bulk conductivity of the region containing the melt, which leads us to propose that the anomalous conductivity in this region is due to partial melt associated with the volcanism. Here we test this hypothesis by using magnetotelluric data recorded at a network of 85 locations in the area of the high-conductivity anomaly. Our data reveal that a localized zone of high conductivity beneath this volcano extends downwards to join the mid-crustal conductor. As our measurements were made during the recent period of lava extrusion at Mount St Helens, we infer that the conductivity anomaly associated with the localized zone, and by extension with the mid-crustal conductor, is caused by the presence of partial melt. Our interpretation is consistent with the crustal origin of silicic magmas erupting from Mount St Helens, and explains the distribution of seismicity observed at the time of the catastrophic eruption in 1980 (refs 9, 10).

Preliminary Spreadsheet of Eruption Source Parameters for Volcanoes of the World

USGS Publications Warehouse

Mastin, Larry G.; Guffanti, Marianne; Ewert, John W.; Spiegel, Jessica

2009-01-01

Volcanic eruptions that spew tephra into the atmosphere pose a hazard to jet aircraft. For this reason, the International Civil Aviation Organization (ICAO) has designated nine Volcanic Ash and Aviation Centers (VAACs) around the world whose purpose is to track ash clouds from eruptions and notify aircraft so that they may avoid these ash clouds. During eruptions, VAACs and their collaborators run volcanic-ashtransport- and-dispersion (VATD) models that forecast the location and movement of ash clouds. These models require as input parameters the plume height H, the mass-eruption rate , duration D, erupted volume V (in cubic kilometers of bubble-free or 'dense rock equivalent' [DRE] magma), and the mass fraction of erupted tephra with a particle size smaller than 63 um (m63). Some parameters, such as mass-eruption rate and mass fraction of fine debris, are not obtainable by direct observation; others, such as plume height or duration, are obtainable from observations but may be unavailable in the early hours of an eruption when VATD models are being initiated. For this reason, ash-cloud modelers need to have at their disposal source parameters for a particular volcano that are based on its recent eruptive history and represent the most likely anticipated eruption. They also need source parameters that encompass the range of uncertainty in eruption size or characteristics. In spring of 2007, a workshop was held at the U.S. Geological Survey (USGS) Cascades Volcano Observatory to derive a protocol for assigning eruption source parameters to ash-cloud models during eruptions. The protocol derived from this effort was published by Mastin and others (in press), along with a world map displaying the assigned eruption type for each of the world's volcanoes. Their report, however, did not include the assigned eruption types in tabular form. Therefore, this Open-File Report presents that table in the form of an Excel spreadsheet. These assignments are preliminary and will be modified to follow upcoming recommendations by the volcanological and aviation communities.

Volcanic evolution of central Basse-Terre Island revisited on the basis of new geochronology and geomorphology data

NASA Astrophysics Data System (ADS)

Ricci, J.; Quidelleur, X.; Lahitte, P.

2015-10-01

Twenty-six new and seven previous K-Ar ages obtained on groundmass separates for samples from the Axial Chain massif (Guadeloupe, F.W.I.), associated with geomorphological investigations, allow us to propose a new model of the volcanic evolution of the central part of Basse-Terre Island. The Axial Chain is composed of four edifices, Moustique, Matéliane, Capesterre, and Icaque mounts, showing coeval activity from 681 ± 12 to 509 ± 10 ka, which contradicts a previous hypothesis that flank collapse affected them successively. Our geomorphological reconstruction shows that the Axial Chain can be considered as a single large volcano, named the Southern Axial Chain volcano (SCA), rather than a succession of several smaller volcanoes. It raises questions regarding the formation of a large depression within the SCA volcano, prior to the construction of the Sans-Toucher volcano between 451 ± 13 and 412 ± 8 ka. Given presently available evidence, a slump affecting the western part of the SCA volcano is the most probable scenario to reconcile the complete age dataset and the present-day morphology of central Basse-Terre. Finally, our study shows that the SCA volcano had a post-activity volume of 90 km3, implying a construction rate of 0.5 km3/kyr. This value strongly constrains interpretations of magma generation processes throughout the Lesser Antilles arc.

Real-Time Data Received from Mount Erebus Volcano, Antarctica

NASA Astrophysics Data System (ADS)

Aster, Richard; McIntosh, William; Kyle, Philip; Esser, Richard; Bartel, Beth Ann; Dunbar, Nelia; Johns, Bjorn; Johnson, Jeffrey B.; Karstens, Richard; Kurnik, Chuck; McGowan, Murray; McNamara, Sara; Meertens, Chuck; Pauley, Bruce; Richmond, Matt; Ruiz, Mario

2004-03-01

Internal and eruptive volcano processes involve complex interactions of multi-phase fluids with the solid Earth and the atmosphere, and produce diverse geochemical, visible, thermal, elastic, and anelastic effects. Multidisciplinary experimental agendas are increasingly being employed to meet the challenge of understanding active volcanoes and their hazards [e.g., Ripepe et al., 2002; Wallace et al., 2003]. Mount Erebus is a large (3794 m) stratovolcano that forms the centerpiece of Ross Island, Antarctica, the site of the principal U.S. (McMurdo) and New Zealand (Scott) Antarctic bases. With an elevation of 3794 m and a volume of ~1670 km3, Erebus offers exceptional opportunities for extended study of volcano processes because of its persistent, low-level, strombolian activity (Volcano Explosivity Index 0-1) and exposed summit magma reservoir (manifested as a long-lived phonolitic lava lake). Key scientific questions include linking conduit processes to near-field deformations [e.g., Aster et al., 2003], explosion physics [e.g., Johnson et al., 2003], magmatic differentiation and residence [e.g., Kyle et al., 1992], and effects on Antarctic atmospheric and ice geochemistry [e.g., Zreda-Gostynska et al., 1997]. The close proximity of Erebus (35 km) to McMurdo, and its characteristic dry, windy, cold, and high-elevation Antarctic environment, make the volcano a convenient test bed for the general development of volcano surveillance and other instrumentation under extreme conditions.

Recent Seismicity in the Ceboruco Volcano, Western Mexico

NASA Astrophysics Data System (ADS)

Nunez, D.; Chávez-Méndez, M. I.; Nuñez-Cornu, F. J.; Sandoval, J. M.; Rodriguez-Ayala, N. A.; Trejo-Gomez, E.

2017-12-01

The Ceboruco volcano is the largest (2280 m.a.s.l) of several volcanoes along the Tepic-Zacoalco rift zone in Nayarit state (Mexico). During the last 1000 years, this volcano had effusive-explosive episodes with eight eruptions providing an average of one eruption each 125 years. Since the last eruption occurred in 1870, 147 years ago, a new eruption likelihood is really high and dangerous due to nearby population centers, important roads and lifelines that traverse the volcano's slopes. This hazards indicates the importance of monitoring the seismicity associated with the Ceboruco volcano whose ongoing activity is evidenced by fumaroles and earthquakes. During 2003 and 2008, this region was registered by just one Lennartz Marslite seismograph featuring a Lennartz Le3D sensor (1 Hz) [Rodríguez Uribe et al. (2013)] where they observed that seismicity rates and stresses appear to be increasing indicating higher levels of activity within the volcano. Until July 2017, a semi-permanent network with three Taurus (Nanometrics) and one Q330 Quanterra (Kinemetrics) digitizers with Lennartz 3Dlite sensors of 1 Hz natural frequency was registering in the area. In this study, we present the most recent seismicity obtained by the semi-permanent network and a temporary network of 21 Obsidians 4X and 8X (Kinemetrics) covering an area of 16 km x 16 km with one station every 2.5-3 km recording from November 2016 to July 2017.

Prediction of ground motion and dynamic stress change in Baekdusan (Changbaishan) volcano caused by a North Korean nuclear explosion

PubMed Central

Hong, Tae-Kyung; Choi, Eunseo; Park, Seongjun; Shin, Jin Soo

2016-01-01

Strong ground motions induce large dynamic stress changes that may disturb the magma chamber of a volcano, thus accelerating the volcanic activity. An underground nuclear explosion test near an active volcano constitutes a direct treat to the volcano. This study examined the dynamic stress changes of the magma chamber of Baekdusan (Changbaishan) that can be induced by hypothetical North Korean nuclear explosions. Seismic waveforms for hypothetical underground nuclear explosions at North Korean test site were calculated by using an empirical Green’s function approach based on a source-spectral model of a nuclear explosion; such a technique is efficient for regions containing poorly constrained velocity structures. The peak ground motions around the volcano were estimated from empirical strong-motion attenuation curves. A hypothetical M7.0 North Korean underground nuclear explosion may produce peak ground accelerations of 0.1684 m/s2 in the horizontal direction and 0.0917 m/s2 in the vertical direction around the volcano, inducing peak dynamic stress change of 67 kPa on the volcano surface and ~120 kPa in the spherical magma chamber. North Korean underground nuclear explosions with magnitudes of 5.0–7.6 may induce overpressure in the magma chamber of several tens to hundreds of kilopascals. PMID:26884136

Operational Monitoring of Volcanoes Using Keyhole Markup Language

NASA Astrophysics Data System (ADS)

Dehn, J.; Bailey, J. E.; Webley, P.

2007-12-01

Volcanoes are some of the most geologically powerful, dynamic, visually appealing structures on the Earth's landscape. Volcanic eruptions are hard to predict, difficult to quantify and impossible to prevent, making effective monitoring a difficult proposition. In Alaska, volcanoes are an intrinsic part of the culture, with over 100 volcanoes and volcanic fields that have been active in historic time monitored by the Alaska Volcano Observatory (AVO). Observations and research are performed using a suite of methods and tools in the fields of remote sensing, seismology, geodesy and geology, producing large volumes of geospatial data. Keyhole Markup Language (KML) offers a context in which these different, and in the past disparate, data can be displayed simultaneously. Dynamic links keep these data current, allowing it to be used in an operational capacity. KML is used to display information from the aviation color codes and activity alert levels for volcanoes to locations of thermal anomalies, earthquake locations and ash plume modeling. The dynamic refresh and time primitive are used to display volcano webcam and satellite image overlays in near real-time. In addition a virtual globe browser using KML, such as Google Earth, provides an interface to further information using the hyperlink, rich- text and flash-embedding abilities supported within object description balloons. By merging these data sets in an easy to use interface, a virtual globe browser provides a better tool for scientists and emergency managers alike to mitigate volcanic crises.

Earth observations taken by the Expedition 14 crew

NASA Image and Video Library

2007-03-21

ISS014-E-17165 (21 March 2007) --- A plume at Shiveluch Volcano, Kamchatka Peninsula, Russia is featured in this image photographed by an Expedition 14 crewmember on the International Space Station. Shiveluch, one of Kamchatka's most active volcanoes, began its latest activity with gas and steam emissions in mid-late March 2007. This image was captured around mid-morning on or around March 21 2007, and shows a steam plume, probably containing minor amounts of ash, blowing westward from the summit of the volcano. The crewmembers were transiting the southern tip of Russia's Kamchatka Peninsula; with a clear view of the volcano about 5 degrees north of the ground track of the station. Subsequent eruptions on March 29 and 30 have been recorded by the Kamchatka Volcano Observatory and NASA. The volcano's southern flank, clearly visible in this northeast-looking oblique view, comprises a horseshoe-shaped caldera from a late Pleistocene eruption, subsequently blanketed by additional ash deposits, and highlighted by the snow cover. The peak of Shiveluch is a distinctive brown color due to the removal of snow, exposure of rock forming the summit, and deposits of new ash. The relatively smooth landscape of the south contrasts with the large, steep valleys on the northern slope of the volcano. Low clouds wrap around the eastern part of the mountain, obscuring the lower elevations.

Volcaniclastic stratigraphy of Gede volcano in West Java

NASA Astrophysics Data System (ADS)

Belousov, A.; Belousova, M.; Zaennudin, A.; Prambada, O.

2012-12-01

Gede volcano (2958 m a.s.l.) and the adjacent Pangrango volcano (3019 m a.s.l.) form large (base diameter 35 km) volcanic massif 60 km south of Jakarta. While Pangrango has no recorded eruptions, Gede is one of the most active volcanoes in Indonesia: eruptions were reported 26 times starting from 1747 (Petroeschevsky 1943; van Bemmelen 1949). Historic eruptions were mildly explosive (Vulcanian) with at least one lava flow. Modern activity of the volcano includes persistent solfataric activity in the summit crater and periodic seismic swarms - in 1990, 1991, 1992, 1995, 1996, 1997, 2000, 2010, and 2012 (CVGHM). Lands around the Gede-Pangrango massif are densely populated with villages up to 1500-2000 m a.s.l. Higher, the volcano is covered by rain forest of the Gede-Pangrango Natural Park, which is visited every day by numerous tourists who camp in the summit area. We report the results of the detailed reinvestigation of volcaniclastic stratigraphy of Gede volcano. This work has allowed us to obtain 24 new radiocarbon dates for the area. As a result the timing and character of activity of Gede in Holocene has been revealed. The edifice of Gede volcano consists of main stratocone (Gumuruh) with 1.8 km-wide summit caldera; intra-caldera lava cone (Gede proper) with a 900 m wide summit crater, having 2 breaches toward N-NE; and intra-crater infill (lava dome/flow capped with 3 small craters surrounded by pyroclastic aprons). The Gumuruh edifice, composed mostly of lava flows, comprises more than 90% of the total volume of the volcano. Deep weathering of rocks and thick (2-4 m) red laterite soil covering Gumuruh indicates its very old age. Attempts to get 14C dates in 4 different locations of Gumuruh (including a large debris avalanche deposit on its SE foot) provided ages older than 45,000 years - beyond the limit for 14C dating. Outside the summit caldera, notable volumes of fresh, 14C datable volcaniclastic deposits were found only in the NNE sector of the volcano where they form a fan below the breached summit crater. The fan is composed of pyroclastic flows (PFs) and lahars of Holocene age that were deposited in 4 major stages: ~ 10 000 BP - voluminous PF of black scoria; ~ 4000 BP - two PFs of mingled grey/black scoria; ~ 1200 BP - multiple voluminous PFs strongly enriched by accidental material; ~ 1000 BP - a small scale debris avalanche (breaching of the crater wall) followed by small scale PFs of black scoria. The intra-crater lava dome/flow was erupted in 1840 (Petroeschevsky, 1943). Three small craters on the top of the lava dome were formed by multiple post-1840 small-scale phreatomagmatic eruptions. Ejected pyroclasts are lithic hydrothermally altered material containing a few breadcrust bombs. The Holocene eruptive history of Gede indicates that the volcano can produce moderately strong (VEI 3-4) explosive eruptions and send PFs and lahars onto the NE foot of the volcano.

Current and future trends of Volcanology in Italy and abroad

NASA Astrophysics Data System (ADS)

Papale, P.

2010-12-01

Volcanology in Italy and in the world has rapidly developed during last decades. In the Seventies, stratigraphy and petrology provided the basic knowledge on the volcanic activities that still forms the root for modern volcano research. During the Eighties and Nineties the interest was more on the quantitative description of the volcanic processes, with enormous progresses in different but complementary fields including laboratory measurements and experiments, physico-mathematical modeling and numerical simulations, geophysical surveys and inverse analysis, and volcano monitoring and surveillance. In year 2000 a large number of magma properties and magmatic and volcanic processes was characterized at a first or higher order. Volcano research in Italy during the first decade of the new millennium has further developed along those lines. To-date, the very high risk Campi Flegrei and Vesuvius volcanoes, and the less risky but permanently active Etna and Stromboli volcanoes, are among the best monitored and more deeply investigated worldwide. The last decade has also seen coordinated efforts aimed at exploring exploitation of knowledge and skills for the benefit of the society. A series of projects focused on volcanic hazard and risk have joined >1000 researchers from Italian and foreign (Europe, US, Japan) Universities and Research Centers, on themes and objectives jointly defined by scientists from INGV and end-users from the national Civil Protection Department. These projects provide a global picture of volcano research in year 2010, that appears to be evolving through i) further rapid developments in the fields of investigation listed above, ii) their merging into effective multidisciplinary approaches, and iii) the full inclusion of the concepts of uncertainty and probabilities in volcanic scenario predictions and hazard forecast. The latter reflects the large inaccessibility of the volcanic systems, the extreme non-linear behaviour of volcanic processes put in light by the numerical studies, and the need of communicating in a formal and structured way the uncertain nature of volcanic predictions to emergency management authorities. Projections to year 2020 suggest a progressive relevance of structured volcano databases, that will provide large-scale sharing of basic knowledge and data for statistical analyses as for epidemiological databases in medicine; full coverage of the frequency range of geophysical and geochemical signals at active volcanoes, today not yet fully achieved; the development of standard volcano models and of global volcano simulator resources and tools, allowing separate sets of observations to be organized in a consistent global picture of the volcano dynamics; the further development of methods for the evaluation of probabilistic scenarios and their organization in event tree systems and hazard forecasting tools; the creation of large-scale volcano infrastructures for sharing of laboratory and computational resources; and the definition of international best practices for volcanic hazard and risk evaluation and for emergency preparedness and response activities. Recent initiatives in Italy and Europe (e.g., EPOS, DIVO, INGV-DPC, Exploris, and others) are developing largely along those lines, providing a view of the expected progresses in volcanology in the next decade.

The critical role of volcano monitoring in risk reduction

USGS Publications Warehouse

Tilling, R.I.

2008-01-01

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

Threshold cascades with response heterogeneity in multiplex networks

NASA Astrophysics Data System (ADS)

Lee, Kyu-Min; Brummitt, Charles D.; Goh, K.-I.

2014-12-01

Threshold cascade models have been used to describe the spread of behavior in social networks and cascades of default in financial networks. In some cases, these networks may have multiple kinds of interactions, such as distinct types of social ties or distinct types of financial liabilities; furthermore, nodes may respond in different ways to influence from their neighbors of multiple types. To start to capture such settings in a stylized way, we generalize a threshold cascade model to a multiplex network in which nodes follow one of two response rules: some nodes activate when, in at least one layer, a large enough fraction of neighbors is active, while the other nodes activate when, in all layers, a large enough fraction of neighbors is active. Varying the fractions of nodes following either rule facilitates or inhibits cascades. Near the inhibition regime, global cascades appear discontinuously as the network density increases; however, the cascade grows more slowly over time. This behavior suggests a way in which various collective phenomena in the real world could appear abruptly yet slowly.

Under trees and water at Crater Lake National Park, Oregon

USGS Publications Warehouse

Robinson, Joel E.; Bacon, Charles R.; Wayne, Chris

2012-01-01

Crater Lake partially fills the caldera that formed approximately 7,700 years ago during the eruption of a 12,000-ft-high volcano known as Mount Mazama. The caldera-forming, or climactic, eruption of Mount Mazama devastated the surrounding landscape, left a thick deposit of pumice and ash in adjacent valleys, and spread a blanket of volcanic ash as far away as southern Canada. Prior to the climactic event, Mount Mazama had a 400,000-year history of volcanic activity similar to other large Cascade volcanoes such as Mounts Shasta, Hood, and Rainier. Since the caldera formed, many smaller, less violent eruptions occurred at volcanic vents below Crater Lake's surface, including Wizard Island. A survey of Crater Lake National Park with airborne LiDAR (Light Detection And Ranging) resulted in a digital elevation map of the ground surface beneath the forest canopy. The average resolution is 1.6 laser returns per square meter yielding vertical and horizontal accuracies of ±5 cm. The map of the floor beneath the surface of the 1,947-ft-deep (593-m-deep) Crater Lake was developed from a multibeam sonar bathymetric survey and was added to the map to provide a continuous view of the landscape from the highest peak on Mount Scott to the deepest part of Crater Lake. Four enlarged shaded-relief views provide a sampling of features that illustrate the resolution of the LiDAR survey and illustrate its utility in revealing volcanic landforms and subtle features of the climactic eruption deposits. LiDAR's high precision and ability to "see" through the forest canopy reveal features that may not be easily recognized-even when walked over-because their full extent is hidden by vegetation, such as the 1-m-tall arcuate scarp near Castle Creek.

The Boring Volcanic Field of the Portland-Vancouver area, Oregon and Washington: tectonically anomalous forearc volcanism in an urban setting

USGS Publications Warehouse

Evarts, Russell C.; Conrey, Richard M.; Fleck, Robert J.; Hagstrum, Jonathan T.; O'Connor, Jim; Dorsey, Rebecca; Madin, Ian P.

2009-01-01

More than 80 small volcanoes are scattered throughout the Portland-Vancouver metropolitan area of northwestern Oregon and southwestern Washington. These volcanoes constitute the Boring Volcanic Field, which is centered in the Neogene Portland Basin and merges to the east with coeval volcanic centers of the High Cascade volcanic arc. Although the character of volcanic activity is typical of many monogenetic volcanic fields, its tectonic setting is not, being located in the forearc of the Cascadia subduction system well trenchward of the volcanic-arc axis. The history and petrology of this anomalous volcanic field have been elucidated by a comprehensive program of geologic mapping, geochemistry, 40Ar/39Ar geochronology, and paleomag-netic studies. Volcanism began at 2.6 Ma with eruption of low-K tholeiite and related lavas in the southern part of the Portland Basin. At 1.6 Ma, following a hiatus of ~0.8 m.y., similar lavas erupted a few kilometers to the north, after which volcanism became widely dispersed, compositionally variable, and more or less continuous, with an average recurrence interval of 15,000 yr. The youngest centers, 50–130 ka, are found in the northern part of the field. Boring centers are generally monogenetic and mafic but a few larger edifices, ranging from basalt to low-SiO2 andesite, were also constructed. Low-K to high-K calc-alkaline compositions similar to those of the nearby volcanic arc dominate the field, but many centers erupted magmas that exhibit little influence of fluids derived from the subducting slab. The timing and compositional characteristics of Boring volcanism suggest a genetic relationship with late Neogene intra-arc rifting.

Biological Studies on a Live Volcano.

ERIC Educational Resources Information Center

Zipko, Stephen J.

1992-01-01

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

Towards Developing Systematics for Using Periodic Studies of the Hydrothermal Manifestations as Effective Tool for Monitoring Largely 'inaccessible' Volcanoes

NASA Astrophysics Data System (ADS)

Alam, M.

2010-12-01

The San José and Tupungatito volcanoes, located near Santiago (Chile), are the potential hazards, given their geological and historical record of explosive eruptions with pyroclastic flows, most recently in 1960 and 1987 respectively (Global Volcanism Program, Smithsonian Institution). What aggravates the potential risk of these very high (>5290m elevation) snow- and ice-covered volcanoes is their location at the source of relatively narrow mountain drainage systems that feed into the Maipo River, flowing through the southern outskirts of Santiago. Sector-collapse and debris-flow, as a result of volcano-ice/snow interaction, can form lahars causing immense destruction to the life and property in the Maipo Valley (Cajón del Maipo). These lahars can cause submergence and burial of vast downstream areas under several meters thick sediment, as in the case of 1980 eruption of Mount St. Helens, USA. In the event of a major eruption, Santiago city will be at peril, with all the drinking water supply installations either destroyed or contaminated to the extent of being abandoned. Besides, ash and tephra will halt the air traffic in the region, particularly in Santiago-Mendoza sector between Chile and Argentina. In a proposed research project (for which funding is awaited from CONICYT, Chile under its Initiation into Research Funding Competition), hydrothermal systems associated with the aforementioned volcanoes will be periodically studied to monitor these volcanoes, in order to develop a Systematics for using the peripheral hydrothermal manifestations, together with nearby surface water bodies, as means for monitoring the activities of the volcano(es). Basic premise of this proposal is to use the relationship between volcanic and hydrothermal activities. Although this association has been observed at many volcanic centers, no attempt has been made to use this relation effectively as a tool for monitoring the volcanoes. Before an eruption or even with increased solfataric activities, the geochemical signatures of the peripheral hydrothermal systems and nearby surface water bodies change significantly. These geochemical changes can be correlated and verified with the observed volcanic activities. Ground deformation of the volcanoes will be studied through Synthetic Aperture Radar (SAR) Interferometry (InSAR), while thermal infrared remote sensing will be used for monitoring thermal anomalies. The reason for choosing these remote methods over the conventional ground based on-site monitoring, is the difficulty in accessing the aforementioned volcanic centers and risk involved in carrying such instruments for frequent observations, as required for the proposed work. In fact, the idea of developing such a Systematics is because of the risk involved in ground based monitoring of these volcanoes. However, microgravity study, which is relatively easier and safer, will be done to validate the results of the remote sensing studies. The expected outcome of the proposed work will not only help in the mitigation of potential hazard of the aforementioned volcanoes, which are currently unmonitored for the reasons mentioned earlier; but will also serve as a model for monitoring remote and largely ‘inaccessible’ volcanoes elsewhere.

Monitoring crater-wall collapse at active volcanoes: a study of the 12 January 2013 event at Stromboli

NASA Astrophysics Data System (ADS)

Calvari, Sonia; Intrieri, Emanuele; Di Traglia, Federico; Bonaccorso, Alessandro; Casagli, Nicola; Cristaldi, Antonio

2016-05-01

Crater-wall collapses are fairly frequent at active volcanoes and they are normally studied through the analysis of their deposits. In this paper, we present an analysis of the 12 January 2013 crater-wall collapse occurring at Stromboli volcano, investigated by means of a monitoring network comprising visible and infrared webcams and a Ground-Based Interferometric Synthetic Aperture Radar. The network revealed the triggering mechanisms of the collapse, which are comparable to the events that heralded the previous effusive eruptions in 1985, 2002, 2007 and 2014. The collapse occurred during a period of inflation of the summit cone and was preceded by increasing explosive activity and the enlargement of the crater. Weakness of the crater wall, increasing magmastatic pressure within the upper conduit induced by ascending magma and mechanical erosion caused by vent opening at the base of the crater wall and by lava fingering, are considered responsible for triggering the collapse on 12 January 2013 at Stromboli. We suggest that the combination of these factors might be a general mechanism to generate crater-wall collapse at active volcanoes.

Colima Volcano, State of Jalisco, Mexico

NASA Image and Video Library

1991-05-06

STS039-75-101 (28 April-6 May 1991) --- Spending over eight days in Earth orbit, the STS-39 crew was able to return with photographic coverage of highly variegated geographic scenery, including a number of volcanoes such as Mexico's Colima. Located south of Guadalajara, Colima is Mexico's most active volcano. The current activity started in the first part of March 1991 with avalanches occurring, followed by lava extrusion and ash emission. Colima is captured here in action. The steam plume drifts eastward from the 13,325 ft. summit. Scars from recent landslides can be seen on the southwest flank of the summit.

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

USGS Publications Warehouse

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.

Risk management of El Chichón and Tacaná Volcanoes: Lessons learned from past volcanic crises: Chapter 8

USGS Publications Warehouse

De la Cruz-Reyna, Servando; Tilling, Robert I.

2015-01-01

Before 1985, Mexico lacked civil-protection agencies with a mission to prevent and respond to natural and human-caused disasters; thus, the government was unprepared for the sudden eruption of El Chichón Volcano in March–April 1982, which produced the deadliest volcanic disaster in the country’s recorded history (~2,000 fatalities). With the sobering lessons of El Chichón still fresh, scientists and governmental officials had a higher awareness of possible disastrous outcome when Tacaná Volcano began to exhibit unrest in late 1985. Seismic and geochemical studies were quickly initiated to monitor activity. At the same time, scientists worked actively with officials of the Federal and local agencies to develop the “Plan Operativo” (Operational Plan)—expressly designed to effectively communicate hazards information and reduce confusion and panic among the affected population. Even though the volcano-monitoring data obtained during the Tacaná crisis were limited, when used in conjunction with protocols of the Operational Plan, they proved useful in mitigating risk and easing public anxiety. While comprehensive monitoring is not yet available, both El Chichón and Tacaná volcanoes are currently monitored—seismically and geochemically—within the scientific and economic resources available. Numerous post-eruption studies have generated new insights into the volcanic systems that have been factored into subsequent volcano monitoring and hazards assessments. The State of Chiapas is now much better positioned to deal with any future unrest or eruptive activity at El Chichón or Tacaná, both of which at the moment are quiescent as of 2014. Perhaps more importantly, the protocols first tested in 1986 at Tacaná have served as the basis for the development of risk-management practices for hazards from other active and potentially active volcanoes in Mexico. These practices have been most notably employed since 1994 at Volcán Popocatépetl since a major eruption under unfavorable prevailing winds may constitute a substantial threat to densely populated metropolitan Mexico City. While the 1982 El Chichón disaster was a national tragedy, it greatly accelerated volcanic emergency preparedness and multidisciplinary scientific studies of eruptive processes and products, not only at El Chichón but also at other explosive volcanoes in Mexico and elsewhere in the world.

Precursory deformation and depths of magma storage revealed by regional InSAR time series surveys: example of the Indonesian and Mexican volcanic arcs

NASA Astrophysics Data System (ADS)

Chaussard, E.; Amelung, F.; Aoki, Y.

2012-12-01

Despite the threat posed to millions of people living in the vicinity of volcanoes, only a fraction of the worldwide ~800 potentially active arc volcanoes have geodetic monitoring. Indonesian and Mexican volcanoes are sparsely monitored with ground-based methods but especially dangerous, emphasizing the need for remote sensing monitoring. In this study we take advantage of over 1200 ALOS InSAR images to survey the entire west Sunda and Mexican volcanic arcs, covering a total of 500 000 km2. We use 2 years of data to monitor the background activity of the Indonesian arc, and 4 years of data at four volcanic edifices (Sinabung, Kerinci, Merapi, and Agung), as well as 4 years of data to survey the Mexican arc. We derive time-dependent ground deformation data using the Small Baseline technique with DEM error correction. We detect seven volcanoes with significant deformation in the west-Sunda arc: six inflating volcanoes (Sinabung, Kerinci, Slamet, Lawu, Lamongan, and Agung) and one deflating volcano (Anak Krakatau). Three of the six inflating centers erupted during or after the observation period. We detect inflation prior to Sinabung's first Holocene eruption in September 2010, followed by a small deflation of the summit area. A similar signal is observed at Kerinci before and after its April 2009 eruption. We also detect uplift prior to Slamet's eruption in April 2009. Agung, in Bali, whose last eruption was in 1964, has been inflating steadily between mid 2007 and early 2009, followed by a period with little deformation until mid-2011. Inflation not followed by eruption is also observed at Lamongan and Lawu, both historically active centers. The close relation between periods of activity and observed deformation suggests that edifice inflation is of magmatic origin and represents the pressurization of reservoirs caused by ascent of new magma. We model the observed deformation and show that the seven deforming Indonesian volcanoes have shallow magma reservoirs at ~1-3 km depth below the average regional elevation. We compare the deformation-activity relationship observed in the west-Sunda arc with results from the Mexican arc. We also compare the depths of magma storage estimated in each arc and use a global data-set of reservoir depths at arc volcanoes to try to explain the observed regional trends in magma storage depths.

Catalogue of Icelandic Volcanoes

NASA Astrophysics Data System (ADS)

Ilyinskaya, Evgenia; Larsen, Gudrun; Gudmundsson, Magnus T.; Vogfjord, Kristin; Pagneux, Emmanuel; Oddsson, Bjorn; Barsotti, Sara; Karlsdottir, Sigrun

2016-04-01

The Catalogue of Icelandic Volcanoes is a newly developed open-access web resource in English intended to serve as an official source of information about active volcanoes in Iceland and their characteristics. The Catalogue forms a part of an integrated volcanic risk assessment project in Iceland GOSVÁ (commenced in 2012), as well as being part of the effort of FUTUREVOLC (2012-2016) on establishing an Icelandic volcano supersite. Volcanic activity in Iceland occurs on volcanic systems that usually comprise a central volcano and fissure swarm. Over 30 systems have been active during the Holocene (the time since the end of the last glaciation - approximately the last 11,500 years). In the last 50 years, over 20 eruptions have occurred in Iceland displaying very varied activity in terms of eruption styles, eruptive environments, eruptive products and the distribution lava and tephra. Although basaltic eruptions are most common, the majority of eruptions are explosive, not the least due to magma-water interaction in ice-covered volcanoes. Extensive research has taken place on Icelandic volcanism, and the results reported in numerous scientific papers and other publications. In 2010, the International Civil Aviation Organisation (ICAO) funded a 3 year project to collate the current state of knowledge and create a comprehensive catalogue readily available to decision makers, stakeholders and the general public. The work on the Catalogue began in 2011, and was then further supported by the Icelandic government and the EU through the FP7 project FUTUREVOLC. The Catalogue of Icelandic Volcanoes is a collaboration of the Icelandic Meteorological Office (the state volcano observatory), the Institute of Earth Sciences at the University of Iceland, and the Civil Protection Department of the National Commissioner of the Iceland Police, with contributions from a large number of specialists in Iceland and elsewhere. The Catalogue is built up of chapters with texts and various mapped information for each of the 32 volcanic systems. The contributions can be classified into three types: 1. Text and other material (including maps and tephra grain size data) on geological aspects and eruption history. This constitutes the bulk of the information presented in the catalogue. 2. Sub-chapters on current alert level and activity status for each volcanic system, updated automatically with information from the IMO monitoring network. 3. Sub-chapters on eruption scenarios, based on the eruption history. We will showcase the newly opened Catalogue web resource at EGU 2016.

Seismicity pattern: an indicator of source region of volcanism at convergent plate margins

NASA Astrophysics Data System (ADS)

Špičák, Aleš; Hanuš, Václav; Vaněk, Jiří

2004-04-01

The results of detailed investigation into the geometry of distribution of earthquakes around and below the volcanoes Korovin, Cleveland, Makushin, Yake-Dake, Oshima, Lewotobi, Fuego, Sangay, Nisyros and Montagne Pelée at convergent plate margins are presented. The ISC hypocentral determinations for the period 1964-1999, based on data of global seismic network and relocated by Engdahl, van der Hilst and Buland, have been used. The aim of this study has been to contribute to the solution of the problem of location of source regions of primary magma for calc-alkaline volcanoes spatially and genetically related to the process of subduction. Several specific features of seismicity pattern were revealed in this context. (i) A clear occurrence of the intermediate-depth aseismic gap (IDAG) in the Wadati-Benioff zone (WBZ) below all investigated active volcanoes. We interpret this part of the subducted slab, which does not contain any teleseismically recorded earthquake with magnitude greater than 4.0, as a partially melted domain of oceanic lithosphere and as a possible source of primary magma for calc-alkaline volcanoes. (ii) A set of earthquakes in the shape of a seismically active column (SAC) seems to exists in the continental wedge below volcanoes Korovin, Makushin and Sangay. The seismically active columns probably reach from the Earth surface down to the aseismic gap in the Wadati-Benioff zone. This points to the possibility that the upper mantle overlying the subducted slab does not contain large melted domains, displays an intense fracturing and is not likely to represent the site of magma generation. (iii) In the continental wedge below the volcanoes Cleveland, Fuego, Nisyros, Yake-Dake, Oshima and Lewotobi, shallow seismicity occurs down to the depth of 50 km. The domain without any earthquakes between the shallow seismically active column and the aseismic gap in the Wadati-Benioff zone in the depth range of 50-100 km does not exclude the melting of the mantle also above the slab. (iv) Any earthquake does not exist in the lithospheric wedge below the volcano Montagne Pelée. The source of primary magma could be located in the subducted slab as well as in the overlying mantle wedge. (v) Frequent aftershock sequences accompanying stronger earthquakes in the seismically active columns indicate high fracturing of the wedge below active volcanoes. (vi) The elongated shape of clusters of epicentres of earthquakes of seismically active columns, as well as stable parameters of the available fault plane solutions, seem to reflect the existence of dominant deeply rooted fracture zones below volcanoes. These facts also favour the location of primary magma in the subducting slab rather than in the overlying wedge. We suppose that melts advancing from the slab toward the Earth surface may trigger the observed earthquakes in the continental wedge that is critically pre-stressed by the process of subduction. However, for definitive conclusions it will be necessary to explain the occurrence of earthquake clusters below some volcanoes and the lack of seismicity below others, taking into account the uncertainty of focal depth determination from global seismological data in some regions.

Magma transfer processes at persistently active volcanoes: insights from gravity observations

NASA Astrophysics Data System (ADS)

Locke, Corinne A.; Rymer, Hazel; Cassidy, John

2003-09-01

Magma transfer processes at persistently active volcanoes are distinguished by the large magma flux required to sustain the prodigious quantities of heat and gas emitted at the surface. Although the resulting degassed magma has been conjectured to accumulate either deep within the volcanic edifice or in the upper levels of the sub-edifice system, no direct evidence for such active accumulation has been reported. Temporal gravity data are unique in being able to quantify mass changes and have been successfully used to model shallow magma movements on different temporal scales, but have not generally been applied to the investigation of postulated long-term accumulation of magma at greater spatial scales within volcanic systems. Here, we model the critical data acquisition parameters required to detect mass flux at volcanoes, we review existing data from a number of volcanoes that exemplify the measurement of shallow mass changes and present new data from Poas and Telica volcanoes. We show that if a substantial proportion of degassed magma lodges within the sub-edifice region, it would result in measurable annual to decadal gravity increases occurring over spatial scales of tens of kilometres and propose that existing microgravity data from Sakurajima and, possibly, Etna volcanoes could be interpreted in these terms. Furthermore, such repeat microgravity data could be used to determine whether the accumulation rate is in equilibrium with the rate of production of degassed magma as calculated from the surface gas flux and hence identify the build-up of gas-rich magma at depth that may be significant in terms of eruption potential. We also argue that large magma bodies, both molten and frozen, modelled beneath volcanoes from seismic and gravity data, could represent endogenous or cryptic intrusions of degassed magma based on order of magnitude calculations using present-day emission rates and typical volcano lifetimes.

Alaska - Russian Far East connection in volcano research and monitoring

NASA Astrophysics Data System (ADS)

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

2012-12-01

The Kurile-Kamchatka-Alaska portion of the Pacific Rim of Fire spans for nearly 5400 km. It includes more than 80 active volcanoes and averages 4-6 eruptions per year. Resulting ash clouds travel for hundreds to thousands of kilometers defying political borders. To mitigate volcano hazard to aviation and local communities, the Alaska Volcano Observatory (AVO) and the Institute of Volcanology and Seismology (IVS), in partnership with the Kamchatkan Branch of the Geophysical Survey of the Russian Academy of Sciences (KBGS), have established a collaborative program with three integrated components: (1) volcano monitoring with rapid information exchange, (2) cooperation in research projects at active volcanoes, and (3) volcanological field schools for students and young scientists. Cooperation in volcano monitoring includes dissemination of daily information on the state of volcanic activity in neighboring regions, satellite and visual data exchange, as well as sharing expertise and technologies between AVO and the Kamchatkan Volcanic Eruption Response Team (KVERT) and Sakhalin Volcanic Eruption Response Team (SVERT). Collaboration in scientific research is best illustrated by involvement of AVO, IVS, and KBGS faculty and graduate students in mutual international studies. One of the most recent examples is the NSF-funded Partnerships for International Research and Education (PIRE)-Kamchatka project focusing on multi-disciplinary study of Bezymianny volcano in Kamchatka. This international project is one of many that have been initiated as a direct result of a bi-annual series of meetings known as Japan-Kamchatka-Alaska Subduction Processes (JKASP) workshops that we organize together with colleagues from Hokkaido University, Japan. The most recent JKASP meeting was held in August 2011 in Petropavlovsk-Kamchatsky and brought together more than 130 scientists and students from Russia, Japan, and the United States. The key educational component of our collaborative program is the continuous series of international volcanological field schools organized in partnership with the Kamchatka State University. Each year more than 40 students and young scientists participate in our annual field trips to Katmai, Alaska and Mutnovsky, Kamchatka.

Volcanic unrest in Kenya: geological history from a satellite perspective

NASA Astrophysics Data System (ADS)

Robertson, E.; Biggs, J.; Edmonds, M.; Vye-Brown, C.

2013-12-01

The East African Rift (EAR) system is a 5,000 km long series of fault bounded depressions that run from Djibouti to Mozambique. In the Kenyan Rift, fourteen Quaternary volcanoes lie along the central rift axis. These volcanoes are principally composed of trachyte pyroclastics and trachyte and basaltic lavas forming low-angle multi-vent edifices. Between 1997 and 2008, geodetic activity has been observed at five Kenyan volcanoes, all of which have undergone periods of caldera collapse and explosive activity. We present a remote-sensing study to investigate the temporal and spatial development of volcanic activity at Longonot volcano. High-resolution mapping using ArcGIS and an immersive 3D visualisation suite (GeovisionaryTM) has been used with imagery derived from ASTER, SPOT5 and GDEM data to identify boundaries of eruptive units and establish relative age in order to add further detail to Longonot's recent eruptive history. Mapping of the deposits at Longonot is key to understand the recent geological history and forms the basis for future volcanic hazard research to inform risk assessments and mitigation programs in Kenya. Calderas at Kenyan volcanoes are elliptical in plan view and we use high-resolution imagery to investigate the regional stresses and structural control leading to the formation of these elliptical calderas. We find that volcanoes in the central and northern segments of the Kenyan rift are elongated nearly parallel to the direction of least horizontal compressive stress, likely as a reflection of the direction of the plate motion vector at the time of caldera collapse. The southern volcanoes however are elongated at an acute angle to the plate motion vector, most likely as a result of oblique opening of the Kenyan rift in this region.

Reunion Island Volcano Erupts

NASA Technical Reports Server (NTRS)

2002-01-01

On January 16, 2002, lava that had begun flowing on January 5 from the Piton de la Fournaise volcano on the French island of Reunion abruptly decreased, marking the end of the volcano's most recent eruption. These false color MODIS images of Reunion, located off the southeastern coast of Madagascar in the Indian Ocean, were captured on the last day of the eruption (top) and two days later (bottom). The volcano itself is located on the southeast side of the island and is dark brown compared to the surrounding green vegetation. Beneath clouds (light blue) and smoke, MODIS detected the hot lava pouring down the volcano's flanks into the Indian Ocean. The heat, detected by MODIS at 2.1 um, has been colored red in the January 16 image, and is absent from the lower image, taken two days later on January 18, suggesting the lava had cooled considerably even in that short time. Earthquake activity on the northeast flank continued even after the eruption had stopped, but by January 21 had dropped to a sufficiently low enough level that the 24-hour surveillance by the local observatory was suspended. Reunion is essentially all volcano, with the northwest portion of the island built on the remains of an extinct volcano, and the southeast half built on the basaltic shield of 8,630-foot Piton de la Fournaise. A basaltic shield volcano is one with a broad, gentle slope built by the eruption of fluid basalt lava. Basalt lava flows easily across the ground remaining hot and fluid for long distances, and so they often result in enormous, low-angle cones. The Piton de la Fournaise is one of Earth's most active volcanoes, erupting over 150 times in the last few hundred years, and it has been the subject of NASA research because of its likeness to the volcanoes of Mars. Image courtesy Jacques Descloitres, MODIS Land Rapid Response Team at NASA GSFC

Effects of Volcanoes on the Natural Environment

NASA Technical Reports Server (NTRS)

Mouginis-Mark, Peter J.

2005-01-01

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

Lahar Hazards at Concepción volcano, Nicaragua

USGS Publications Warehouse

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

2001-01-01

Concepción is one of Nicaragua’s highest and most active volcanoes. The symmetrical cone occupies the northeastern half of a dumbbell shaped island called Isla Ometepa. The dormant volcano, Maderas, occupies the southwest half of the island. A narrow isthmus connects Concepción and Maderas volcanoes. Concepción volcano towers more than 1600 m above Lake Nicaragua and is within 5 to 10 km of several small towns situated on its aprons at or near the shoreline. These towns have a combined population of nearly 5,000. The volcano has frequently produced debris flows (watery flows of mud, rock, and debris—also known as lahars when they occur on a volcano) that could inundate these nearby populated areas. Concepción volcano has erupted more than 25 times in the last 120 years. Its first recorded activity was in AD 1883. Eruptions in the past century, most of which have originated from a small summit crater, comprise moderate explosions, ash that falls out of eruption plumes (called tephra), and occasional lava flows. Near the summit area, there are accumulations of rock that were emplaced hot (pyroclastic deposits), most of which were hot enough to stick together during deposition (a process called welding). These pyroclastic rocks are rather weak, and tend to break apart easily. The loose volcanic rock remobilizes during heavy rain to form lahars. Volcanic explosions have produced blankets of tephra that are distributed downwind, which on Isla Ometepe is mostly to the west. Older deposits at the west end of the island that are up to 1 m thick indicate larger explosive events have happened at Concepción volcano in prehistoric time. Like pyroclastic-flow deposits, loose tephra on the steep slopes of the volcano provides source material that heavy rainstorms and earthquakes can mobilize to trigger debris flow.

Earth Observation taken by the Expedition 25 crew

NASA Image and Video Library

2010-11-19

ISS025-E-017440 (19 Nov. 2010) --- Kamchatka volcanoes are featured in this image photographed by an Expedition 25 crew member on the International Space Station. This striking photograph features several snow-covered volcanoes located on the Kamchatka Peninsula of the Russian Federation, as seen from the orbital perspective of the International Space Station (ISS). This image also illustrates one of the unique attributes provided by the ISS – the ability to view Earth landscapes at an angle, rather than the “straight down” view typical of many orbital satellite-based sensors. This oblique view, together with shadows cast by the volcanoes and other mountains provides perspective about the setting and a sense of topography of the region, especially highlighting the symmetrical cones of Kronotsky (center) and Kizimen (top right) stratovolcanoes. Kizimen Volcano last erupted in 1928, while Kronotsky Volcano—one of the largest on the peninsula—last erupted in 1923. Schmidt Volcano, located to the north of Kronotsky, has the morphology of a shield volcano and is not known to have erupted during the period of historical record. To the south of Kronotsky is Krasheninnikov Volcano, comprised of two overlapping stratovolcanoes that formed within an earlier caldera. Scientists believe Krasheninnikov may have last erupted in 1550. The two summit craters of the stratovolcanoes are clearly visible in this image (lower left). Lake Kronotsky (left) is Kamchatka’s largest lake; it was formed when lava flows from Kronotsky Volcano dammed the Listvenichnaya River. The Kamchatka Peninsula lies along the so-called “Ring of Fire” in the Pacific Ocean. The Ring of Fire is characterized by the presence of active volcanoes and frequent earthquakes; these are associated with the many active subduction and transform boundary zones that ring the Pacific tectonic plate. According to scientists, there are currently 114 volcanoes identified on the Kamchatka Peninsula that have erupted during the Holocene Epoch (approximately 12,000 years ago to the present).

Systematic Satellite Observations of the Impact of Aerosols from Passive Volcanic Degassing on Local Cloud Properties

NASA Technical Reports Server (NTRS)

Ebmeier, S.K.; Sayer, Andrew M.; Grainger, R. G.; Mather, T. A.; Carboni, E.

2014-01-01

The impact of volcanic emissions, especially from passive degassing and minor explosions, is a source of uncertainty in estimations of aerosol indirect effects. Observations of the impact of volcanic aerosol on clouds contribute to our understanding of both present-day atmospheric properties and of the pre-industrial baseline necessary to assess aerosol radiative forcing. We present systematic measurements over several years at multiple active and inactive volcanic islands in regions of low present-day aerosol burden. The timeaveraged indirect aerosol effects within 200 kilometers downwind of island volcanoes are observed using Moderate Resolution Imaging Spectroradiometer (MODIS, 2002-2013) and Advanced Along-Track Scanning Radiometer (AATSR, 2002- 2008) data. Retrievals of aerosol and cloud properties at Kilauea (Hawaii), Yasur (Vanuatu) and Piton de la Fournaise (la Reunion) are rotated about the volcanic vent to be parallel to wind direction, so that upwind and downwind retrievals can be compared. The emissions from all three volcanoes - including those from passive degassing, Strombolian activity and minor explosions - lead to measurably increased aerosol optical depth downwind of the active vent. Average cloud droplet effective radius is lower downwind of the volcano in all cases, with the peak difference ranging from 2 - 8 micrometers at the different volcanoes in different seasons. Estimations of the difference in Top of Atmosphere upward Short Wave flux upwind and downwind of the active volcanoes from NASA's Clouds and the Earth's Radiant Energy System (CERES) suggest a downwind elevation of between 10 and 45 Watts per square meter at distances of 150 - 400 kilometers from the volcano, with much greater local (less than 80 kilometers) effects. Comparison of these observations with cloud properties at isolated islands without degassing or erupting volcanoes suggests that these patterns are not purely orographic in origin. Our observations of unpolluted, isolated marine settings may capture processes similar to those in the pre-industrial marine atmosphere.

U.S. Geological Survey (USGS) Western Region Kasatochi Volcano Coastal and Ocean Science

USGS Publications Warehouse

DeGange, Anthony

2010-01-01

Alaska is noteworthy as a region of frequent seismic and volcanic activity. The region contains 52 historically active volcanoes, 14 of which have had at least one major eruptive event since 1990. Despite the high frequency of volcanic activity in Alaska, comprehensive studies of how ecosystems respond to volcanic eruptions are non-existent. On August 7, 2008, Kasatochi Volcano, in the central Aleutian Islands, erupted catastrophically, covering the island with ash and hot pyroclastic flow material. Kasatochi Island was an annual monitoring site of the U.S. Fish and Wildlife Service, Alaska Maritime National Wildlife Refuge (AMNWR); therefore, features of the terrestrial and nearshore ecosystems of the island were well known. In 2009, the U.S. Geological Survey (USGS), AMNWR, and University of Alaska Fairbanks began long-term studies to better understand the effects of the eruption and the role of volcanism in structuring ecosystems in the Aleutian Islands, a volcano-dominated region with high natural resource values.

Sulfur dioxide emissions from la soufriere volcano, st. Vincent, west indies.

PubMed

Hoff, R M; Gallant, A J

1980-08-22

During the steady-state period of activity of La Soufriere Volcano in 1979, the mass emissions of sulfur dioxide into the troposphere amounted to a mean value of 339 +/- 126 metric tons per day. This value is similar to the sulfur dioxide emissions of other Central American volcanoes but less than those measured at Mount Etna, an exceptionally strong volcanic source of sulfur dioxide.

Insights on volcanic behaviour from the 2015 July 23-24 T-phase signals generated by eruptions at Kick-'em-Jenny Submarine Volcano, Grenada, Lesser Antilles

NASA Astrophysics Data System (ADS)

Dondin, F. J. Y.; Latchman, J. L.; Robertson, R. E. A.; Lynch, L.; Stewart, R.; Smith, P.; Ramsingh, C.; Nath, N.; Ramsingh, H.; Ash, C.

2015-12-01

Kick-'em-Jenny volcano (KeJ) is the only known active submarine volcano in the Lesser Antilles Arc. Since 1939, the year it revealed itself, and until the volcano-seismic unrest of 2015 July 11-25 , the volcano has erupted 12 times. Only two eruptions breached the surface: 1939, 1974. The volcano has an average eruption cycle of about 10-11 years. Excluding the Montserrat, Soufrière Hills, KeJ is the most active volcano in the Lesser Antilles arc. The University of the West Indies, Seismic Research Centre (SRC) has been monitoring KeJ since 1953. On July 23 and 24 at 1:42 am and 0:02 am local time, respectively, the SRC recorded T-phase signals , considered to have been generated by KeJ. Both signals were recorded at seismic stations in and north of Grenada: SRC seismic stations as well as the French volcano observatories in Guadeloupe and Martinique, Montserrat Volcano Observatory, and the Puerto Rico Seismic Network. These distant recordings, along with the experience of similar observations in previous eruptions, allowed the SRC to confirm that two explosive eruptions occurred in this episode at KeJ. Up to two days after the second eruption, when aerial surveillance was done, there was no evidence of activity at the surface. During the instrumental era, eruptions of the KeJ have been identified from T-phases recorded at seismic stations from Trinidad, in the south, to Puerto Rico, in the north. In the 2015 July eruption episode, the seismic station in Trinidad did not record T-phases associated with the KeJ eruptions. In this study we compare the T-phase signals of 2015 July with those recorded in KeJ eruptions up to 1974 to explore possible causative features for the T-phase recording pattern in KeJ eruptions. In particular, we investigate the potential role played by the Sound Fixing and Ranging (SOFAR) layer in influencing the absence of the T-phase on the Trinidad seismic station during this eruption.

Methanogenic activity and diversity in the centre of the Amsterdam Mud Volcano, Eastern Mediterranean Sea.

PubMed

Lazar, Cassandre Sara; John Parkes, R; Cragg, Barry A; L'Haridon, Stephane; Toffin, Laurent

2012-07-01

Marine mud volcanoes are geological structures emitting large amounts of methane from their active centres. The Amsterdam mud volcano (AMV), located in the Anaximander Mountains south of Turkey, is characterized by intense active methane seepage produced in part by methanogens. To date, information about the diversity or the metabolic pathways used by the methanogens in active centres of marine mud volcanoes is limited. (14)C-radiotracer measurements showed that methylamines/methanol, H(2)/CO(2) and acetate were used for methanogenesis in the AMV. Methylotrophic methanogenesis was measured all along the sediment core, Methanosarcinales affiliated sequences were detected using archaeal 16S PCR-DGGE and mcrA gene libraries, and enrichments of methanogens showed the presence of Methanococcoides in the shallow sediment layers. Overall acetoclastic methanogenesis was higher than hydrogenotrophic methanogenesis, which is unusual for cold seep sediments. Interestingly, acetate porewater concentrations were extremely high in the AMV sediments. This might be the result of organic matter cracking in deeper hotter sediment layers. Methane was also produced from hexadecanes. For the most part, the methanogenic community diversity was in accordance with the depth distribution of the H(2)/CO(2) and acetate methanogenesis. These results demonstrate the importance of methanogenic communities in the centres of marine mud volcanoes. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

Earth Observations taken by Expedition 34 crewmember

NASA Image and Video Library

2012-11-30

ISS034-E-005496 (30 Nov. 2012) --- An eruption at the Ulawun volcano, New Britain Island, Papua New Guinea is featured in this image photographed by an Expedition 34 crew member on the International Space Station. Numerous volcanoes contribute to the landmass of the island of New Britain, the largest in the Bismarck Archipelago of Papua New Guinea. One of the most active of these volcanoes, Ulawun, is also the highest with a summit elevation of 2,334 meters. This photograph was taken during the most recent phase of volcanic activity at Ulawun. A white steam and ash plume extends from the summit crater of the stratovolcano towards the northwest (center; note the image is oriented such that north is towards the lower left). The plume begins to broaden as it passes the southwestern coast of Lolobau Island approximately 23 kilometers downwind from its source. Ulawun volcano is also known as “the Father”, with the Bamus volcano to the southwest also known as “the South Son”. The summit of Bamus is obscured by white cumulus clouds (not of volcanic origin) in this image. While Ulawun has been active since at least 1700, the most recent eruptive activity at Bamus occurred in the late 19th century. A large region of ocean surface highlighted by sunglint – sunlight reflecting off the water surface, lending it a mirror-like appearance– is visible to the north-northeast of Ulawun (lower left).

Linear scaling relationships and volcano plots in homogeneous catalysis – revisiting the Suzuki reaction† †Electronic supplementary information (ESI) available: Detailed derivation of the linear scaling relationships and construction of the volcano plots as well as comparisons of computed values using PBE0-dDsC and M06 functionals is included. See DOI: 10.1039/c5sc02910d Click here for additional data file.

PubMed Central

Busch, Michael; Wodrich, Matthew D.

2015-01-01

Linear free energy scaling relationships and volcano plots are common tools used to identify potential heterogeneous catalysts for myriad applications. Despite the striking simplicity and predictive power of volcano plots, they remain unknown in homogeneous catalysis. Here, we construct volcano plots to analyze a prototypical reaction from homogeneous catalysis, the Suzuki cross-coupling of olefins. Volcano plots succeed both in discriminating amongst different catalysts and reproducing experimentally known trends, which serves as validation of the model for this proof-of-principle example. These findings indicate that the combination of linear scaling relationships and volcano plots could serve as a valuable methodology for identifying homogeneous catalysts possessing a desired activity through a priori computational screening. PMID:28757966

Exploring the "Sharkcano": Biogeochemical observations of the Kavachi submarine volcano (Solomon Islands) using simple, cost-effective methods.

NASA Astrophysics Data System (ADS)

Phillips, B. T.; Albert, S.; Carey, S.; DeCiccio, A.; Dunbabin, M.; Flinders, A. F.; Grinham, A. R.; Henning, B.; Howell, C.; Kelley, K. A.; Scott, J. J.

2015-12-01

Kavachi is a highly active undersea volcano located in the Western Province of the Solomon Islands, known for its frequent phreatomagmatic eruptions and ephemeral island-forming activity. The remote location of Kavachi and its explosive behavior has restricted scientific exploration of the volcano, limiting observations to surface imagery and peripheral water-column data. An expedition to Kavachi in January 2015 was timed with a rare lull in volcanic activity, allowing for observation of the inside of Kavachi's caldera and its flanks. Here we present medium-resolution bathymetry of the main peak paired with benthic imagery, petrologic analysis of samples from the caldera rim, measurements of gas flux over the main peak, and hydrothermal plume structure data. A second peak was discovered to the Southwest of the main cone and displayed evidence of diffuse-flow venting. Populations of gelatinous animals, small fish, and sharks were observed inside the active crater, raising new questions about the ecology of active submarine volcanoes. Most equipment used in this study was lightweight, relatively low-cost, and deployed using small boats; these methods may offer developing nations an economic means to explore deep-sea environments within their own territorial waters.

Volcano-Tectonic Activity at Deception Island Volcano Following a Seismic Swarm in the Bransfield Rift (2014-2015)

NASA Astrophysics Data System (ADS)

Almendros, J.; Carmona, E.; Jiménez, V.; Díaz-Moreno, A.; Lorenzo, F.

2018-05-01

In September 2014 there was a sharp increase in the seismic activity of the Bransfield Strait, Antarctica. More than 9,000 earthquakes with magnitudes up to 4.6 located SE of Livingston Island were detected over a period of 8 months. A few months after the series onset, local seismicity at the nearby (˜35 km) Deception Island volcano increased, displaying enhanced long-period seismicity and several outbursts of volcano-tectonic (VT) earthquakes. Before February 2015, VT earthquakes occurred mainly at 5-20 km SW of Deception Island. In mid-February the numbers and sizes of VT earthquakes escalated, and their locations encompassed the whole volcanic edifice, suggesting a situation of generalized unrest. The activity continued in anomalously high levels at least until May 2015. Given the spatial and temporal coincidence, it is unlikely that the Livingston series and the Deception VT swarm were unrelated. We propose that the Livingston series may have produced a triggering effect on Deception Island volcano. Dynamic stresses associated to the seismic swarm may have induced overpressure in the unstable volcanic system, leading to a magmatic intrusion that may in turn have triggered the VT swarm. Alternatively, both the Livingston earthquakes and the VT swarm could be consequences of a magmatic intrusion at Deception Island. The Livingston series would be an example of precursory distal VT swarm, which seems to be a common feature preceding volcanic eruptions and magma intrusions in long-dormant volcanoes.

Observing changes at Santiaguito Volcano, Guatemala with an Unmanned Aerial Vehicle (UAV)

NASA Astrophysics Data System (ADS)

De Angelis, S.; von Aulock, F.; Lavallée, Y.; Hornby, A. J.; Kennedy, B.; Lamb, O. D.; Kendrick, J. E.

2016-12-01

Santiaguito Volcano (Guatemala) is one of the most active volcanoes in Central America, producing several ash venting explosions per day for almost 100 years. Lahars, lava flows and dome and flank collapses that produce major pyroclastic density currents also present a major hazard to nearby farms and communities. Optical observations of both the vent as well as the lava flow fronts can provide scientists and local monitoring staff with important information on the current state of volcanic activity and hazard. Due to the strong activity, and difficult terrain, unmanned aerial vehicles can help to provide valuable data on the activities of the volcano at a safe distance. We collected a series of images and video footage of the active vent of Caliente and the flow front of the active lava flow and its associated lahar channels, both in May 2015 and in December 2015- January 2016. Images of the crater and the lava flows were used for the reconstruction of 3D terrain models using structure-from-motion. These models can be used to constrain topographical changes and distribution of ballistics via cloud comparisons. The preliminary data of aerial images and videos of the summit crater (during two separate ash venting episodes) and the lava flow fronts indicate the following differences in activity during those two field campaigns: - A recorded explosive event in December 2015 initiates at subparallel linear faults near the centre of the dome, with a later, separate, and more ash-laden burst occurring from an off-centre fracture. - A comparison of the point clouds before and after a degassing explosion shows minor subsidence of the dome surface and the formation of several small craters at the main venting locations. - The lava flow fronts did not advance more than a few meters between May and December 2015. - Damming of river valleys by the lava flows has established new stream channels that have modified established pathways for the recurring lahars, one of the major hazards of Santiaguito volcano. The preliminary results of this study from two fieldtrips to Santiaguito Volcano are exemplary for the plethora of applications of UAVs in the field of volcano monitoring, and we urge funding agencies and legislative bodies to consider the value of these scientific instruments in future decisions and allocation of funding.

An alternative modeling framework for better interpretation of the observed volcano-hydrothermal system data

NASA Astrophysics Data System (ADS)

Yue, Z. Q. Q.

2015-12-01

Many phenomena and data related to volcanoes and volcano eruptions have been observed and collected over the past four hundred years. They have been interpreted with the conventional and widely accepted hypothesis or theory of hot magma fluid from mantle. However, the prediction of volcano eruption sometimes is incorrect. For example, the devastating eruption of the Mount Ontake on Sept. 27, 2014 was not predicted and/or warned at all, which caused 55 fatalities, 9 missing and more than 60 injured. Therefore, there is a need to reconsider the cause and mechanism of active volcano and its hydrothermal system. On the basis of more than 30 year study and research in geology, volcano, earthquake, geomechanics, geophysics, geochemistry and geohazards, the author has developed a new and alternative modeling framework (or hypothesis) to better interpret the observed volcano-hydrothermal system data and to more accurately predict the occurrence of volcano explosion. An active volcano forms a cone-shape mountain and has a crater with vertical pipe conduit to allow hot lava, volcanic ash and gases to escape or erupt from its chamber (Figure). The chamber locates several kilometers below the ground rocks. The active volcanos are caused by highly compressed and dense gases escaped from the Mantle of the Earth. The gases are mainly CH4 and further trapped in the upper crustal rock mass. They make chemical reactions with the surrounding rocks in the chamber. The chemical reactions are the types of reduction and decomposition. The reactions change the gas chemical compounds into steam water gas H2O, CO2, H2S, SO2 and others. The oxygen in the chemical reaction comes from the surrounding rocks. So, the product lava has a less amount of oxygen than that of the surrounding rocks. The gas-rock chemical reactions produce heat. The gas expansion and penetration power and the heat further break and crack the surrounding rock mass and make them into lavas, fragments, ashes or bombs. The pyroclastic deposits are carried out of the chamber by the gas expansion and uplift power and form the cone-shape mountain. The crust loses its rocks and the chamber becomes larger and larger. Eventually, the last eruption occurs and breaks the upper rocks and the cone mountain. The pyroclatic rocks collapse into the chamber space and leave a basin or lake.

Eruption mechanism as inferred from geomagnetic changes with special attention to the 1989 1990 activity of Aso volcano

NASA Astrophysics Data System (ADS)

Tanaka, Yoshikazu

1993-06-01

Geomagnetic changes associated with the volcanic activity of Aso volcano were detected with a dense network of continuously recording proton-precession magnetometers during the period from June 1989 to June 1990. Magnetic date clearly indicate that changes in the magnetization within the volcano are most probably caused by temperature changes. This activity can be divided into five stages, which are characterized by magnetization and demagnetization of the volcano. These magnetic changes with durations of a few months are definitely correlated with some typical volcanic events at the crater as well as the volcanic tremor activity. The demagnetization stage appears when the vent is covered by a water pool or the volcanic activity is enhanced. The magnetization stage follows the opening of a vent and several large explosions which make the vent permeable. The source of magnetic changes lies at a depth of about 200 m below the crater rim in the southwestern part of the active crater. Magnetic moments responsible for observed magnetic changes at stages 1, 2 and 4 are 3.4, -5.2 and -2.2 Wbm, respectively. The corresponding source volume is estimated as a single sphere of radius 40-50 m or a spherical shell of 100 m or so. An effective mechanism of rapid heating/cooling exists, which is ascribed to the interaction of groundwater and superheated vapor, i.e., a shallow hydrothermal system. This hydrothermal system driven by the surface cap of the vent, controls every feature of the eruptions at the final outlet of Aso volcano.

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

NASA Astrophysics Data System (ADS)

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.

Active Volcano Monitoring using a Space-based Hyperspectral Imager

NASA Astrophysics Data System (ADS)

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 JPL Publ. 96-4, vol. 1, pp. 105-113. Lockwood, Ronald B., Thomas W. Cooley, Richard M. Nadile, James A. Gardner, Peter S. Armstrong, Abraham M. Payton, Thom M. Davis, Stanley D. Straight, Thomas G. Chrien, Edward L. Gussin, and David Makowski (2006). Advanced Responsive Tactically-Effective Military Imaging Spectrometer (ARTEMIS) Design, in Proceedings of the 2006 IEEE International Geoscience and Remote Sensing Symposium, 31 July-4 August 2006, Denver, Colorado. Ramsey, Michael S., and Luke P. Flynn (2004). Strategies, insights, and the recent advances in volcanic monitoring and mapping with data from NASA’s Earth Observing System, Jour. of Volcanology and Geothermal Research, vol. 135, pp. 1-11. Young, Joseph (2009). EO-1 Weekly status report for September 24-30, 2009, Earth Science Mission Operations (ESMO) Office, NASA Goddard Space Flight Center, Greenbelt, MD 20771.

A Discrete Dynamical System Approach to Pathway Activation Profiles of Signaling Cascades.

PubMed

Catozzi, S; Sepulchre, J-A

2017-08-01

In living organisms, cascades of covalent modification cycles are one of the major intracellular signaling mechanisms, allowing to transduce physical or chemical stimuli of the external world into variations of activated biochemical species within the cell. In this paper, we develop a novel method to study the stimulus-response of signaling cascades and overall the concept of pathway activation profile which is, for a given stimulus, the sequence of activated proteins at each tier of the cascade. Our approach is based on a correspondence that we establish between the stationary states of a cascade and pieces of orbits of a 2D discrete dynamical system. The study of its possible phase portraits in function of the biochemical parameters, and in particular of the contraction/expansion properties around the fixed points of this discrete map, as well as their bifurcations, yields a classification of the cascade tiers into three main types, whose biological impact within a signaling network is examined. In particular, our approach enables to discuss quantitatively the notion of cascade amplification/attenuation from this new perspective. The method allows also to study the interplay between forward and "retroactive" signaling, i.e., the upstream influence of an inhibiting drug bound to the last tier of the cascade.

Preliminary volcano-hazard assessment for Aniakchak Volcano, Alaska

USGS Publications Warehouse

Neal, Christina A.; McGimsey, Robert G.; Miller, Thomas P.; Riehle, James R.; Waythomas, Christopher F.

2000-01-01

Aniakchak is an active volcano located on the Alaska Peninsula 670 kilometers southwest of Anchorage. The volcano consists of a dramatic, 10-kilometer-diameter, 0.5 to 1.0-kilometer-deep caldera that formed during a catastrophic eruption 3,500 years ago. Since then, at least a dozen separate vents within the caldera have erupted, often explosively, to produce lava flows and widespread tephra (ash) deposits. The most recent eruption at Aniakchak occurred in 1931 and was one of the largest explosive eruptions in Alaska in the last 100 years. Although Aniakchak volcano presently shows no signs of unrest, explosive and nonexplosive eruptions will occur in the future. Awareness of the hazards posed by future eruptions is a key factor in minimizing impact.

Lahar hazards at Agua volcano, Guatemala

USGS Publications Warehouse

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

2001-01-01

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

2006 Volcanic Activity in Alaska, Kamchatka, and the Kurile Islands: Summary of Events and Response of the Alaska Volcano Observatory

USGS Publications Warehouse

Neal, Christina A.; McGimsey, Robert G.; Dixon, James P.; Manevich, Alexander; Rybin, Alexander

2008-01-01

The Alaska Volcano Observatory (AVO) responded to eruptions, possible eruptions, and volcanic unrest at or near nine separate volcanic centers in Alaska during 2006. A significant explosive eruption at Augustine Volcano in Cook Inlet marked the first eruption within several hundred kilometers of principal population centers in Alaska since 1992. Glaciated Fourpeaked Mountain, a volcano thought to have been inactive in the Holocene, produced a phreatic eruption in the fall of 2006 and continued to emit copious amounts of volcanic gas into 2007. AVO staff also participated in hazard communication and monitoring of multiple eruptions at seven volcanoes in Russia as part of its collaborative role in the Kamchatka and Sakhalin Volcanic Eruption Response Teams.

SAR measurements of surface displacements at Augustine Volcano, Alaska from 1992 to 2005

USGS Publications Warehouse

Lee, C.-W.; Lu, Z.; Kwoun, Oh-Ig

2007-01-01

Augustine volcano is an active stratovolcano located at the southwest of Anchorage, Alaska. Augustine volcano had experienced seven significantly explosive eruptions in 1812, 1883, 1908, 1935, 1963, 1976, and 1986, and a minor eruption in January 2006. We measured the surface displacements of the volcano by radar interferometry and GPS before and after the eruption in 2006. ERS-1/2, RADARSAT-1 and ENVISAT SAR data were used for the study. Multiple interferograms were stacked to reduce artifacts caused by different atmospheric conditions. Least square (LS) method was used to reduce atmospheric artifacts. Singular value decomposition (SVD) method was applied for retrieval of time sequential deformations. Satellite radar interferometry helps to understand the surface displacements system of Augustine volcano. ?? 2007 IEEE.

SAR measurements of surface displacements at Augustine Volcano, Alaska from 1992 to 2005

USGS Publications Warehouse

Lee, C.-W.; Lu, Z.; Kwoun, Oh-Ig

2008-01-01

Augustine volcano is an active stratovolcano located at the southwest of Anchorage, Alaska. Augustine volcano had experienced seven significantly explosive eruptions in 1812, 1883, 1908, 1935, 1963, 1976, and 1986, and a minor eruption in January 2006. We measured the surface displacements of the volcano by radar interferometry and GPS before and after the eruption in 2006. ERS-1/2, RADARSAT-1 and ENVISAT SAR data were used for the study. Multiple interferograms were stacked to reduce artifacts caused by different atmospheric conditions. Least square (LS) method was used to reduce atmospheric artifacts. Singular value decomposition (SVD) method was applied for retrieval of time sequential deformations. Satellite radar interferometry helps to understand the surface displacements system of Augustine volcano. ?? 2007 IEEE.

Introduction to section 2. Climax-stage magmatism: Growth history Of Kilauea Volcano and its instability

NASA Astrophysics Data System (ADS)

Lipman, Peter W.

On the south flank of Hawai'i Island, frequent eruptions, abundant earthquakes, and rapid ground deformation mark the current locus of volcanism along the Hawaiian Ridge. Kïlauea and Mauna Loa volcanoes are in a tholeiitic shield-building stage, erupting mainly on land. South of Kïlauea, Lö'ihi Seamount has erupted alkalic and transitional basalts that mark the growth of Hawai`i's youngest volcano. Kïlauea is the most active volcano on Earth, and its summit caldera and two rift zones characterize the typical shield stage of Hawaiian volcanoes. Kïlauea's south flank, between the rift zones, is subject to sustained and episodic seaward displacements associated with frequent earthquakes and expressed on land by the Hilina fault system.

Strategies for the implementation of a European Volcano Observations Research Infrastructure

NASA Astrophysics Data System (ADS)

Puglisi, Giuseppe

2015-04-01

Active volcanic areas in Europe constitute a direct threat to millions of people on both the continent and adjacent islands. Furthermore, eruptions of "European" volcanoes in overseas territories, such as in the West Indies, an in the Indian and Pacific oceans, can have a much broader impacts, outside Europe. Volcano Observatories (VO), which undertake volcano monitoring under governmental mandate and Volcanological Research Institutions (VRI; such as university departments, laboratories, etc.) manage networks on European volcanoes consisting of thousands of stations or sites where volcanological parameters are either continuously or periodically measured. These sites are equipped with instruments for geophysical (seismic, geodetic, gravimetric, electromagnetic), geochemical (volcanic plumes, fumaroles, groundwater, rivers, soils), environmental observations (e.g. meteorological and air quality parameters), including prototype deployment. VOs and VRIs also operate laboratories for sample analysis (rocks, gases, isotopes, etc.), near-real time analysis of space-borne data (SAR, thermal imagery, SO2 and ash), as well as high-performance computing centres; all providing high-quality information on the current status of European volcanoes and the geodynamic background of the surrounding areas. This large and high-quality deployment of monitoring systems, focused on a specific geophysical target (volcanoes), together with the wide volcanological phenomena of European volcanoes (which cover all the known volcano types) represent a unique opportunity to fundamentally improve the knowledge base of volcano behaviour. The existing arrangement of national infrastructures (i.e. VO and VRI) appears to be too fragmented to be considered as a unique distributed infrastructure. Therefore, the main effort planned in the framework of the EPOS-PP proposal is focused on the creation of services aimed at providing an improved and more efficient access to the volcanological facilities and observations on active volcanoes. The issue to facilitate the access to this valued source of information is to reshape this fragmented community into a unique infrastructure concerning common technical solutions and data policies. Some of the key actions include the implementation of virtual accesses to geophysical, geochemical, volcanological and environmental raw data and metadata, multidisciplinary volcanic and hazard products, tools for modelling volcanic processes, and transnational access to facilities of volcano observatories. Indeed this implementation will start from the outcomes of the two EC-FP7 projects, Futurevolc and MED-SUV, relevant to three out of four global volcanic Supersites, which are located in Europe and managed by European institutions. This approach will ease the exchange and collaboration among the European volcano community, thus allowing better understanding of the volcanic processes occurring at European volcanoes considered worldwide as natural laboratories.

Morphological analysis of Cerro Bravo Volcano, Central Andes of Colombia

NASA Astrophysics Data System (ADS)

Arango-Palacio, E.; Murcia, H. F.; Robayo, C.; Chica, P.; Piedrahita, D. A.; Aguilar-Casallas, C.

2017-12-01

Keywords: Cerro Bravo Volcano, Volcanic landforms, Craters. Cerro Bravo Volcano (CBV) belongs to the San Diego-Cerro Machín Volcano - Tectonic Province in the Central Andes of Colombia. CVB is located 150 km NW from Bogotá, the capital of Colombia, and 25 km E from Manizales city ( 350,00 inhabitants). The volcanic activity of CBV began at 50,000 years ago and has been characterized by produce effusive and explosive (subplinian to plinian) eruptions with dacitic and andesitic in composition products. The effusive activity is evidenced by lava flows and lava domes, while the explosive activity is evidenced by pyroclastic density current deposits and pyroclastic fall deposits; some secondary deposits such as debris avalanches and lahares has been also recognised. Currently, the CBV is considered as a hazard for the Manizales city. In order to characterise the volcanic edifice, a morphological analysis was carried out and a map was created from a digital elevations model (DEM) with 12.5 m resolution as well as aerial photographs. Thus, it was possible to associate the landforms with the evolution of the volcano. Based on this analysis, it was possible to identify the base and top of the CBV edifice as 2400 and 4020 m.a.s.l., respectively, with a diameter in its major axis of 5.8 km. The volcanic edifice has four main craters opening to the north. The craters are apart from each other by heights and distances between 120 m.a.s.l. and 1 km, respectively; this geomorphology is an evidence of different eruptive stages of the volcano construction. Morphological analysis has shown that some craters were created from explosive eruptions, however the different heights between each crater suggest the creation of lava domes and their collapse as a response of the final effusive activity.

Analysis of GPS Data Using Near Real-Time Data from the Volcano Exploration Project in the Community College Classroom (Invited)

NASA Astrophysics Data System (ADS)

House, M.; Nagy-Shadman, E.; Wilbur, B.

2010-12-01

Using real-time data or near-real-time data in the classroom is an exciting prospect in Introductory Physical Geology courses, especially since it promises to offer students a chance to experience the excitement and uncertainty associated with the study of the natural world that appeals to so many of their instructors. However, there are several obstacles to this approach in the community college. Namely, many introductory level community college earth science courses have no mathematics prerequisites; as such, a typical classroom may include a wide range of mathematical skills and many students may be unable to participate in the analysis of “real” data. Further, reliable computer access to websites offering real-time data can be spotty at some institutions and for some students on home computers. In response to this problem we have created a multipart volcano monitoring activity based on the USGS Volcano Exploration Project: Pu`u `O`o (VEPP) website. This activity is designed for freshman or sophomore level courses in Introductory Geology or Geological Hazards for non-majors. No prior math skills are assumed; the activity can be completed without prior knowledge of GPS data, volcano monitoring or Hawaiian geology. The activity consists of three parts: (1) a background lecture on basic geology of volcanoes like Kilauea and use of GPS in volcano monitoring; (2) a lab activity or a homework assignment based on near real-time data downloaded from the VEPP website; and (3) a group wrap-up that focuses on real-time data by exploring other aspects of the VEPP website. The lab activity requires examination of downloaded GPS time series data for a specified time period (this can be modified as desired by the instructor), computation of displacements, graphing of displacement vectors for identified time intervals and determination of actual motion vectors, followed by a discussion of the displacements observed. These activities are interspersed by guided questions. This activity will be tested for the first time in Introductory Physical Geology courses at Pasadena City College during Fall 2010.

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

NASA Astrophysics Data System (ADS)

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

2018-03-01

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

The chronology of the martian volcanoes

NASA Technical Reports Server (NTRS)

Plescia, J. B.; Saunders, R. S.

1979-01-01

The volcanoes of Mars have been divided into three groups based on morphology: basaltic shields, domes and composite cones, and highland patera. A fourth group can be added to include the volcano-tectonic depressions. Using crater counts and the absolute chronology of Soderblom, an attempt is made to estimate the history of the volcanoes. Early in the martian history, about 2.5 b.y. ago, all three styles of volcanoes were active at various locations on the surface. At approximately 1.7-1.8 b.y. ago a transition occurred in the style and loci of volcanic construction. Volcanoes of younger age appear to be only of the basaltic shield group and are restricted to the Tharsis region. This same transition was noted by a change in the style of the basaltic shield group. Older shields were small low features, while the younger shields are significantly broader and taller.

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

NASA Astrophysics Data System (ADS)

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

2013-12-01

An InSAR survey of all 13 Holocene volcanoes in the Andean Central Volcanic Zone of Peru reveals previously undocumented surface deformation that is occasionally accompanied by seismic activity. Our survey utilizes SAR data spanning from 1992 to the present from the ERS-1, ERS-2, and Envisat satellites, as well as selected data from the TerraSAR-X satellite. We find that the recent unrest at Sabancaya volcano (heightened seismicity since 22 February 2013 and increased fumarolic output) has been accompanied by surface deformation. We also find two distinct deformation episodes near Sabancaya that are likely associated with an earthquake swarm in February 2013 and a M6 normal fault earthquake that occurred on 17 July 2013. Preliminary modeling suggests that faulting from the observed seismic moment can account for nearly all of the observed deformation and thus we have not yet found clear evidence for recent magma intrusion. We also document an earlier episode of deformation that occurred between December 2002 and September 2003 which may be associated with a M5.3 earthquake that occurred on 13 December 2002 on the Solarpampa fault, a large EW-striking normal fault located about 25 km northwest of Sabancaya volcano. All of the deformation episodes between 2002 and 2013 are spatially distinct from the inflation seen near Sabancaya from 1992 to 1997. In addition to the activity at Sabancaya, we also observe deformation near Coropuna volcano, in the Andagua Valley, and in the region between Ticsani and Tutupaca volcanoes. InSAR images reveal surface deformation that is possibly related to an earthquake swarm near Coropuna and Sabancaya volcanoes in December 2001. We also find persistent deformation in the scoria cone and lava field along the Andagua Valley, located 40 km east of Corpuna. An earthquake swarm near Ticsani volcano in 2005 produced surface deformation centered northwest of the volcano and was accompanied by a north-south elongated subsidence signal to the southeast. We investigate a possible relationship between the seismicity and the subsidence and find that the swarm generates a stress field which may encourage the opening of fractures oriented parallel to both the elongation of the subsidence signal and the trend of regional faults. Thus, we hypothesize that the Ticsani swarm triggered the subsidence to the southeast by allowing migration of hydrothermal fluids through cracks, similar to the volcanic subsidence observed in southern Chile following the 2010 Maule earthquake and in Japan following the 2011 Tohoku earthquake, though other explanations for the subsidence cannot be ruled out. A noteworthy null result of our InSAR survey is the lack of deformation at Ubinas volcano, one of the most active volcanoes in Peru, even spanning its 2006 eruption.

NASA Spacecraft Spots Large Eruption of Russian Volcano

NASA Image and Video Library

2012-06-07

NASA Terra spacecraft acquired this image on June 2, 2012 of Sheveluch, one of the most active volcanoes on the Kamchatka peninsula, with frequent explosive events that can disrupt air traffic over the northern Pacific.

Investigation of Aceh Segment and Seulimeum Fault by using seismological data; A preliminary result

NASA Astrophysics Data System (ADS)

Muksin, U.; Irwandi; Rusydy, I.; Muzli; Erbas, K.; Marwan; Asrillah; Muzakir; Ismail, N.

2018-04-01

The Seulimeum Fault has not generated large earthquake after last large earthquake with magnitude of M 7.3 occured in 1936. The Seulimeum Fault is accompanied by the Seulawah volcano that reported to be active in 1839, 1975 and 2010. The activity of the Seulimeum Fault could be related with the existence of the Seulawah volcano and the Seulawah volcano activity could also triggered by the Seulumeum Fault activity. The objective of the longterm research is to investigate the relation between the Seulimeum Fault and the Seulawah Volcano. The aim of this paper is to present the first result of the investigation of the Seulimeum Fault based on the seismicity and geomorphology. A seismic network consisting of 17 seismometers (Trilium Compact) and data logger (DSS Cube) were deployed in Aceh Besar. The seismic network was installed for 3 months to record earthquakes along the Seulimeum and the Aceh Faults. The Seulimeum Fault is considered to be active as several local earthquakes were recorded. The Seulimeum Fault is much more active in the region of the bifurcation of the The Aceh Segment and the Seulimeum Fault. The mechanisms of earthquakes along the Seulimeum Fault were mostly strike slip following similar to the Sumatran Fault characteristics.

Volcan Baru: Eruptive History and Volcano-Hazards Assessment

USGS Publications Warehouse

Sherrod, David R.; Vallance, James W.; Tapia Espinosa, Arkin; McGeehin, John P.

2008-01-01

Volcan Baru is a potentially active volcano in western Panama, about 35 km east of the Costa Rican border. The volcano has had four eruptive episodes during the past 1,600 years, including its most recent eruption about 400?500 years ago. Several other eruptions occurred in the prior 10,000 years. Several seismic swarms in the 20th century and a recent swarm in 2006 serve as reminders of a restless tectonic terrane. Given this history, Volcan Baru likely will erupt again in the near or distant future, following some premonitory period of seismic activity and subtle ground deformation that may last for days or months. Future eruptions will likely be similar to past eruptions?explosive and dangerous to those living on the volcano?s flanks. Outlying towns and cities could endure several years of disruption in the wake of renewed volcanic activity. Described in this open-file report are reconnaissance mapping and stratigraphic studies, radiocarbon dating, lahar-inundation modeling, and hazard-analysis maps. Existing data have been compiled and included to make this report as comprehensive as possible. The report is prepared in coooperation with National Secretariat for Science, Technology and Innovation (SENACYT) of the Republic of Panama and the U.S. Agency for International Development (USAID).

Eruption of Kliuchevskoi volcano

NASA Image and Video Library

1994-10-05

STS068-155-094 (30 September-11 October 1994) --- (Kliuchevskoi Volcano) The crewmembers used a Linhof large format Earth observation camera to photograph this nadir view of the Kamchatka peninsula's week-old volcano. The eruption and the follow-up environmental activity was photographed from 115 nautical miles above Earth. Six NASA astronauts spent a week and a half aboard the Space Shuttle Endeavour in support of the Space Radar Laboratory 2 (SRL-2) mission.

Potential hazards from future eruptions of Mount St. Helens Volcano, Washington

USGS Publications Warehouse

Crandell, Dwight Raymond; Mullineaux, Donal Ray

1978-01-01

Mount St. Helens has been more active and more explosive during the last 4,500 years than any other volcano in the conterminous United States. Eruptions of that period repeatedly formed domes, large volumes of pumice, hot pyroclastic flows, and, during the last 2,500 years, lava flows. Some of this activity resulted in mudflows that extended tens of kilometers down the floors of valleys that head at the volcano. This report describes the nature of the phenomena and their threat to people and property; the accompanying maps show areas likely to be affected by future eruptions of Mount St. Helens. Explosive eruptions that produce large volumes of pumice affect large areas because winds can carry the lightweight material hundreds of kilometers from the volcano. Because of prevailing winds, the 180-degree sector east of the volcano will be affected most often and most severely by future eruptions of this kind. However, the pumice from any one eruption will fall in only a small part of that sector. Pyroclastic flows and mudflows also can affect areas far from the volcano, but the areas they affect are smaller because they follow valleys. Mudflows and possibly pyroclastic flows moving rapidly down Swift and Pine Creeks could displace water in Swift Reservoir, which could cause disastrous floods farther downvalley.

Technical-Information Products for a National Volcano Early Warning System

USGS Publications Warehouse

Guffanti, Marianne; Brantley, Steven R.; Cervelli, Peter F.; Nye, Christopher J.; Serafino, George N.; Siebert, Lee; Venezky, Dina Y.; Wald, Lisa

2007-01-01

Introduction Technical outreach - distinct from general-interest and K-12 educational outreach - for volcanic hazards is aimed at providing usable scientific information about potential or ongoing volcanic activity to public officials, businesses, and individuals in support of their response, preparedness, and mitigation efforts. Within the context of a National Volcano Early Warning System (NVEWS) (Ewert et al., 2005), technical outreach is a critical process, transferring the benefits of enhanced monitoring and hazards research to key constituents who have to initiate actions or make policy decisions to lessen the hazardous impact of volcanic activity. This report discusses recommendations of the Technical-Information Products Working Group convened in 2006 as part of the NVEWS planning process. The basic charge to the Working Group was to identify a web-based, volcanological 'product line' for NVEWS to meet the specific hazard-information needs of technical users. Members of the Working Group were: *Marianne Guffanti (Chair), USGS, Reston VA *Steve Brantley, USGS, Hawaiian Volcano Observatory HI *Peter Cervelli, USGS, Alaska Volcano Observatory, Anchorage AK *Chris Nye, Division of Geological and Geophysical Surveys and Alaska Volcano Observatory, Fairbanks AK *George Serafino, National Oceanic and Atmospheric Administration, Camp Springs MD *Lee Siebert, Smithsonian Institution, Washington DC *Dina Venezky, USGS, Volcano Hazards Team, Menlo Park CA *Lisa Wald, USGS, Earthquake Hazards Program, Golden CO

Volcanology curricula development aided by online educational resource

USGS Publications Warehouse

Poland, Michael P.; van der Hoeven Kraft, Katrien J.; Teasdale, Rachel

2011-01-01

Volcanic activity is an excellent hook for engaging college and university students in geoscience classes. An increasing number of Internet-accessible real-time and near–real time volcano monitoring data are now available and constitute an important resource for geoscience education; however, relatively few data sets are comprehensive, and many lack background information to aid in interpretation. In response to the need for organized, accessible, and well-documented volcano education resources, the U.S. Geological Survey's Hawaiian Volcano Observatory (HVO), in collaboration with NASA and the University of Hawai`i at Manoa, established the Volcanoes Exploration Project: Pu`u `Ō`ō (VEPP). The VEPP Web site (http://vepp.wr.usgs.gov) is an educational resource that provides access, in near real time, to geodetic, seismic, and geologic data from the active Pu`u `Ō`ō eruptive vent on Kilauea volcano, Hawaii, along with background and context information. A strength of the VEPP site is the common theme of the Pu`u `Ō`ō eruption, which allows the site to be revisited multiple times to demonstrate different principles and integrate many aspects of volcanology.