Monday, December 18, 2006
Volcano and Earthquake Monitoring at Yellowstone
Yellowstone National Park is located above one of the largest active volcanic systems in the world. USGS has monitored the area for many years and has published a monitoring plan for 2006-2015 which includes new instrumentation to monitor new locations, collect new types of data and upgrade the current monitoring effort. 
Proposed new stream monitoring, gas sampling, GPS, tilt, seismic and strain monitoring instruments to be added to the Yellowstone volcano and earthquake monitoring network. Thick black line is the boundary of the Yellowstone Caldera. Thin black lines are roads. Gray outline is park boundary. Red regions are thermal areas. Image by USGSYellowstone earthquake monitoring will be upgraded to modern standards and five new seismograph stations will be added to increase the observation density. Five borehole strainmeters and two tiltmeters will be installed to measure crustal movements. New stream gages, and gas-measuring instruments will enable scientists to compare geophysical phenomena, such as earthquakes and ground motions, to hydrothermal events, such as anomalous water and gas discharge. In addition, USGS hopes to characterize the behavior of geyser basins to detect any precursors to hydrothermal explosions and to monitor earthquakes related to fluid movements. Finally, a secure system for real-time transmission of data will ensure that important data is not lost at critical times. Read the entire 17-page report: Volcano and Earthquake Monitoring Plan for the Yellowstone Volcano Observatory, 2006-2015Labels: Earthquakes, Geothermal, Volcanoes
Monday, December 11, 2006
Great Volcano Image
Volcano Image by NASA
Click Image for More Detail
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One of the best satellite images of a volcano that I have ever seen is now on display at NASA's Earth Observatory website. Tungurahua Volcano in Ecuador has been erupting or restless for the past several months. Lava flows and pyroclastics have blanketed much of the surrounding landscape, forced evacuations of many villages, dammed the Chambo River and caused numerous fatalities and injuries. Tungurahua is one of the most active volcanoes in Ecuador, but many people decide to live on its flanks because of the rich soils and mild temperatures. The price for this has been abandonment of property and the risk of injury or death. Visit the Earth Observatory website to see this great Volcano Image. Labels: Satellite-Images, Volcanoes
Sunday, November 26, 2006
Climate Impact of High Latitude Volcanic Eruptions
Researchers in a NASA/NSF/NOAA funded study have identified connections between high latitude volcanic eruptions and periods of low water flow in African rivers. Using computer models they linked Iceland's Laki Volcanic Event (a series of about ten eruptions that occurred between June 1783 and February 1784) to the lowest water levels in the Nile River in a historical record dating back to 622 AD. Using computer models developed by NASA they found that the Laki Volcanic Event altered surface temperature patterns that produced extremely low levels of rainfall across much of Africa. The initial atmospheric response to the eruption was a decline in global temperatures. This temperature decline produced a reduced temperature difference between land and ocean. Without that temperature contrast, onshore winds weakened and the delivery of moisture and rainfall from the ocean was severely reduced. 
Following a volcanic eruption, large amounts of sulfur dioxide (SO2), hydrochloric acid (HCL) and ash are spewed into the Earth's stratosphere. In most cases, HCL condenses with water vapor and is rained out of the volcanic cloud. SO2 from the cloud is transformed into sulfuric acid. The sulfuric acid quickly condenses, producing aerosol particles which linger in the atmosphere for long periods of time. Image and description by NASA/LaRC |
In addition to low flows on the Nile River during 1783 and 1784 in response to the Laki Volcanic Event, low water levels were observed on the Niger River after the Novarupta eruption of 1912, and on the Nile River after the Eldgia (Iceland) eruption of 939 AD. Read more at about the climate impact of high latitude volcanic eruptions at the NASA website. Labels: Arctic-Antarctic, Volcanoes
Saturday, November 18, 2006
New Volcanic Island and Pumice Raft in Tonga
Image by USGS
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In August, crew members of a yacht sailing through the Tonga Islands spotted a massive pumice raft covering several square kilometers of ocean. A pumice raft is a large quantity of pumice fragments floating on the ocean surface (pumice is a volcanic rock that contains so many gas vesicles that it floats). This raft was produced by the eruption of a new volcanic island located about 20 kilometers southwest of Late Island. Pumice rafts are a rare occurrence, seen perhaps once a decade during the eruption of a marine volcano. 
Pumice raft floating near Late Island - Image by NASAThe image above (taken on September 15 - about a month after the eruption) shows the new volcanic island in the southwest corner of the image and the pumice raft to the northwest of Late Island. A trail of pumice connects the raft to Late Island. Read more details and see close-up photos of the pumice raft taken by the yacht crew at Tonga Online. Labels: Volcanoes
Thursday, September 28, 2006
Fourpeaked Volcano Eruption Possible
Fourpeaked Volcano, located near the mouth of Cook Inlet, Alaska is threatening to erupt. Visible unrest began on September 17 with explosions and vigorous emissions of ash, gas and steam from vents on the volcano's flank. Elevated levels of sulfur dioxide, hydrogen sulfide, and carbon dioxide have been detected. 
Steam emissions from Fourpeaked Volcano. Image by Christina Neal, AVO/USGSAccording to USGS, these abundant volcanic gases, the opening of new vents near the summit, and the disruption of glaciers suggest the presence of new magma at shallow depths beneath the volcano. USGS's level of concern color code for the volcano is YELLOW with a possible eruption within the next few days to few weeks. Geologists from the Alaska Volcanic Observatory are monitoring the volcano with satellite data and observation flights. They are also installing seismometers to monitor earthquake activity beneath the volcano. 
Temporary broadband seismometer and time-lapse camera installed on Fourpeaked Volcano.
Image by Rick Wessels, AVO/USGSGet the most recent news about Fourpeaked Volcano at the Alaska Volcano Observatory website. Labels: Volcanoes
Friday, September 01, 2006
Mayon Volcano Hangs on Edge of Eruption
USGS image by C. Newhall - September, 1984
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In early August, the Philippine Institute of Volcanology and Seismology recommended an evacuation of thousands of people who live within a danger zone surrounding Mayon volcano and the Philippine government responded with an evacuation order ( see our previous post). Mayon continues its activity and remains dangerous in the opinion of the PIVS. The evacuated people remain in numerous temporary evacuation centers which provide uncomfortable accommodations which are expensive for the government to maintain. One of the main causes for concern is the possibility of pyroclastic flows (deadly clouds of hot gases and ash that can flow down the flank of the volcano at great speeds and run several miles from the volcano's base). During an eruption in 1993, seventy seven people were killed by Mayon's pyroclastic flows. The images (below and right) show pyroclastic flows descending Mayon during a 1984 eruption. 
USGS image by C. Newhall - September, 1984Read more about Mayon Volcano in a story at Yahoo! News. Labels: Volcanoes
Saturday, August 26, 2006
Santorini Eruption Might Have Been Twice as Powerful
Santorini / Island of Thera - Click to enlarge.
Copyright Geology.com and Map Resources.
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Santorini is a shield volcano in the Aegean Sea about 100 kilometers north of Crete. It is part of the Cyclades volcanic island chain. Santorini volcano has erupted numerous times, producing massive, overlapping calderas at 100,000 years before present, 54,000 YBP, 18,500 YBP and 3,500 YBP. The eruption that produced the youngest caldera destroyed the Minoan civilization on the island of Crete (excavations there suggest that the area was evacuated prior to the eruption - probably by threatening earthquakes and volcanic activity). These events are thought to have sparked the story of the lost civilization of Atlantis. Today, the islands of Thera, Therasia and Aspronisi form the Santorini Archipelago, which surrounds the central, steep-walled caldera bay. A team of Greek and U.S. researchers have completed a seismic survey of the ocean floor in the area of the Santorini Archapelago. Based upon this survey they conclude that the Santorini eruption of 3,500 years ago was about twice as powerful as originally believed. Their estimate places it as the second most powerful eruption in human history, exceeded only by the eruption of Tambora, in Indonesia, in 1815. 
Image by USGSRead National Geographic's account of the Santorini Eruption. Labels: Volcanoes
Thursday, August 17, 2006
Eruption at Tungurahua Volcano Ecuador - Map
Tungurahua Volcano Map.Click
Image to Enlarge. Copyright
Geology.com, Map Resources.
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Tungurahua Volcano, a stratovolcano in central Ecuador is erupting again. This volcano has a history of sudden strong explosions, lava flows, lahars and pyroclastic flows that have reached populated areas near its base. Early this morning Tungurahua erupted with a powerful explosion, launching hot rocks and ash into the air and producing a lava flow that spread into populated areas. Thousands have been evacuated and remain at a safe distance even though the activity subsided quickly. Scientists at the National Geophysics Institute expect more explosive activity over the coming days or weeks. Read more about Tungurahua Volcano at the ABC News website. 
Tungurahua Volcano - 1999 Image by USGSLabels: Volcanoes
Friday, July 21, 2006
Mount Mayon Volcano Eruption
UPDATE: The Philippine Government has ordered the evacuation of about 35,000 people from the immediate area of Mount Mayon. Read more at BBC |
Image after CIA Factbook
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Mount Mayon Volcano, the most active volcano in the Philippines, is currently active, producing ash, lava flows and numerous tremors. Scientists at the Philippine Institute of Volcanology and Seismology believe that a major eruption could occur within the next few weeks. The Philippine government has ordered evacuation of all areas within a six kilometer radius of the volcano and has issued warnings to people living immediately outside of the evacuation zone. This evacuation has involved over 4000 people, however if the alert level increases over 60,000 residents could be ordered to evacuate. Mayon has erupted numerous times in the last few decades with ashfalls, large ash columns, lava flows and pyroclastic flows. Eruption "alerts" have been issued several times since the last major activity in 2001. The volcano has a history of producing deadly pyroclastic flows (see image below from a 1984 eruption). For updates on the Mount Mayon eruption visit the Philippine Institute of Volcanology and Seismology website. 
Image by Earth Observatory
USGS Image by C.G. NewhallLabels: Volcanoes
Tuesday, July 04, 2006
Links Between Global Warming, Volcanoes and Earthquakes?
University of Alberta geologist Patrick Wu hypothesizes that glacial melting due to climate change could cause increased volcanic activity and earthquakes. His linkage between them is the reduction in pressure on land areas as the ice (which can be over 1 KM thick in areas of Greenland and Antarctica) melts, and an increase in pressure upon the sea floor as sea level rises. Many geologists might doubt this relation, however, very broad areas will be exposed to these changes and locations teetering on the verge of eruption or release could be enabled. Alan Glazner of the University of North Carolina reports that he also sees linkages between climate change and volcanic activity. ""When you melt glacial ice, several hundred metres to a kilometre thick . . . you've decreased the load on the crust and so you've decreased the pressure holding the volcanic conduits closed." Read the article "Climate change could cause earthquakes and volcanic eruptions" at K-LightFM.com Labels: Earthquakes, Global-Warming, Volcanoes
Saturday, June 24, 2006
Empedocles: Underwater Volcano off the Coast of Sicily
Empedocles is an underwater volcano located about 25 miles (40 km) off the coast of Sicily. It rises approximately 1300 feet (400 m) above the adjacent ocean floor and its summit is currently about 7 meters (23 feet) below sea level. Empedocles is not newly discovered; instead it is newly understood. 
Image copyright by Geology.com and Map Resources.Historically Empedocles was thought to be a cluster of volcanoes; however, recent studies by Cesare Corselli of the National Interuniversity Consortium For Marine Sciences suggest that it is a single cone that erupts at a central vent or at smaller vents on its flanks. Until recently, Empedocles has fooled scientists. Although Empedocles is currently dormant it has erupted in the recent geologic past. An eruption in the third century BC elevated the volcano to above sea level, forming a small island. An island was also formed during an eruption in 1831. This eruption caused quite a political and military incident when several countries attempted to claim it as their own. Their dispute lasted a few months until subsidence lowered the volcano below sea level. Eruptions at Empedocles are not anticipated in the near future. Labels: Volcanoes
Tuesday, April 25, 2006
Indonesia's Merapi Volcano Threatens Eruption
Mount Merapi, a stratovolcano on the Indonesian island of Java is threatening eruption. The area around Merapi has a high population density. Hundreds of small villages surround the volcano and the province capital of Yogyakarta (home to over 1,000,000 people) is only 18 miles south of the volcano. Merapi has erupted several times this century, sometimes with deadly impact. Lahars and pyroclastic flows have devastated agricultural areas and caused fatalities on the western flank of the mountain. Scars from these lahars can be seen in the Landsat image below. The most deadly event was in 1930 and killed over 1000 people. 
Image by geology.com using NASA Landsat dataRead more at ReliefWeb. Labels: Volcanoes
Monday, April 24, 2006
Tambora Discovery Could Be Pompeii of the East
The 1815 eruption of Mount Tambora on the Indonesian island of Sumbawa was the largest volcanic eruption in Earth's recorded history. It ejected about 50 cubic kilometers of magma and left a deep caldera in the location where a large stratovolcano had stood. Earthquakes from the eruption were felt at Surabaya, approximately 500 kilometers away. The impact of this eruption was global. The powerful eruption launched millions of tons of fine volcanic dust and gases into the atmosphere. Atmospheric circulation disseminated the dust and gases throughout the stratosphere. This significantly reduced the amount of sunlight which reached the Earth and resulted in a temporary decline in global temperatures by as much as 3° C. For nearly a year, most of the northern hemisphere experienced sharply cooler temperatures and the calendar year 1816 has been referred to as the "the year without a summer." A village believed to have been covered by the Tambora eruption has recently been discovered and is now being called "The Pompeii of the East" Read more in a National Geographic Article. Labels: Volcanoes
Saturday, April 08, 2006
Carbon Dioxide Gas Claims Skiers at Mammoth Mountain
Three members of a ski patrol team at Mammoth Mountain, California were asphyxiated by carbon dioxide gas at a vent where they were installing plastic fencing to keep other skiers away. The vent is on the Christmas Bowl run and is known as the "stink hole" because of the bad-smelling gases. Carbon dioxide gas has been a problem at Mammoth Mountain in the past. Large volumes of gas have seeped through the soil and have killed many trees throughout an area of about 100 acres. (The trees need to absorb oxygen directly from the soil and the soil gases in some areas have been largely displaced by carbon dioxide.) These emissions have not caused problems for people as the carbon dioxide is quickly dissipated when it escapes from the soil. Mammoth Mountain is a young volcano on the southwest rim of Long Valley Caldera, a large volcanic depression in eastern California. It has been volcanically active for about 4 million years. The most recent volcanic eruptions in the region occurred about 200 years ago, and earthquakes frequently shake the area. Because of this, the U.S. Geological Survey (USGS) operates an extensive network of instruments to monitor the continuing unrest in the Long Valley area. Read more details about the skiers in an Associated Press story at SFGate.com. Learn more about Mammoth Mountain and previous carbon dioxide emissions at the Long Valley Observatory website. Labels: Volcanoes
Thursday, March 16, 2006
Mount Vesuvius Eruption - Are We Due for Another?
The most famous eruption of Mount Vesuvius took place in 79 AD and destroyed the city of Pompeii. New geological and archaeological discoveries have shown that another major Vesuvius eruption occurred during the Bronze Age (about 4000 years ago) and was even more devastating. Research by Michael Sheridan (University at Buffalo), Giuseppe Mastrolorenzo and Lucia Pappalardo (Istituto Nazionale di Geofisica e Volcanologia-Osservatorio Vesuviano), and Pierpaolo Petrone (Museo di Antropologia. Centro Musei delle Scienze Naturali) documents the impact of the eruption on people living in the area through trackways which include thousands of human and animal footprints, skeletons of people and livestock buried under a meter of pumice and other evidence. Their work shows that the eruption strongly affected the area of what is now metropolitan Naples - much farther away than previously realized - and makes a strong call for reevaluating volcanic risk in the area. Sheridan has studied the history of Vesuvius eruptions and a trend of eruptions at 2000 year intervals can be traced back over 20,000 years. So, the Bronze Age eruption was 4000 years ago, the Pompei eruption was 2000 years ago... are we due for another? Read more about the Bronze Age Mount Vesuvius Eruption at the University at Buffalo website. Labels: Volcanoes
Saturday, March 04, 2006
Uplift at Yellowstone Caldera
USGS has been monitoring surface elevations and ground deformation over Yellowstone Caldera using satellite technologies. Between 1997 and 2003 approximately 12 cm (5 inches) of uplift was detected. 
Image of ground deformation was created with satellite data by USGS
Graph of N-S, E-W and Vertical deformation by USGS
3D image of Yellowstone Caldera by USGSRead more about Yellowstone Caldera. Labels: Volcanoes
Saturday, February 11, 2006
Monitoring Augustine Volcano
USGS now has a website that gives public access to eruption photos and data for Augustine Volcano. Available are hourly observation reports, maps, two webcams, earthquake data and graphs, seismograms, geophysical station maps and much more. Here are a few examples of what you can see at their site. 
Augustine Volcano Photo from the USGS Webcam
Earthquake data from USGSVisit the Augustine Volcano Information page on the USGS website. Labels: Volcanoes
Friday, January 13, 2006
Augustine Volcano Eruption (Alaska)
Augustine Island Volcano, located in southern Cook Inlet, about 100 km WSW of the town of Homer on the Kenai Peninsula and nearly 300 km SW from Anchorage, is erupting now after about 18 years of inactivity. The current eruption is producing ash but USGS is concerned that a large blast might occur. Augustine's symmetrical cone rises 1,254 meters above sea level. It was named by Captain James Cook in 1778 and has erupted in 1812, 1883, 1935, 1963-64, 1976, and 1986. An eruptive blast in 1883 produced a large landslide which ran out to the ocean, extending the island's north shorline as far as 2 kilometers and producing a small tsunami that swept across Cook Inlet. Augustine's 1986 eruption began with a violent explosion on March 26th. This sent ash plumes to more than 10 kilometers above the vent and triggered pyroclastic flows that sped down the volcano's flanks into the sea. A second stage began on April 23 when lava began erupting near the volcano's summit and added about 25 meters to the top of the existing lava dome. Small pyroclastic flows accompanied growth of the dome. 
Image by USGS - 1988
Image by USGS - 1986 ash eruptionLabels: Volcanoes
Saturday, January 07, 2006
Problems Caused by Volcanic Ash
Volcanic ash causes lots of problems where it falls in large quantities. An article at KTUU Channel 2 News tells about the problems caused by volcanic ash and what a person can do to prepare before the eruption begins. Read more about Preparing for a Volcanic Eruption at KTUU.com. Labels: Volcanoes
Saturday, December 24, 2005
Mount Cayley and the 2010 Olympics
An article by Ben Parfitt at straight.com speculates about how a volcanic eruption at Mount Cayley or another volcano in the Garibaldi Volcanic Belt could cause problems for the 2010 Winter Olympics to be held in Vancouver, British Columbia. The article is not a prediction and it does not provide a technical analysis of this situation. However, it is an interesting read because it includes comments from several volcanologists and a non-technical survey of the impacts of previous eruptions in Canada and worldwide. Perhaps the most interesting is a story of an eruption that coincided with the arrival of the first European explorers to the coastal waters of northern British Columbia. Read more at straight.com. Labels: Volcanoes
Tuesday, December 13, 2005
Sounds Beneath the Southern Ocean
Researchers are learning about the sounds beneath the Southern Ocean which surrounds Antarctica. A team from the Oregon State University Hatfield Marine Science Center will record sounds in an area of the Bransfield Straight, between the Antarctic Peninsula and the South Shetland Islands. Their hope is to record moving ice sheets, undersea earthquakes and volcanoes, and vocalizations of baleen whales. 
Southern Ocean Map by CIA Factbook.Read more about this Southern Ocean research at the Newport News-Times website. Labels: Arctic-Antarctic, Volcanoes
Saturday, November 26, 2005
Story of Vesuvius and the Pompeii Eruption
The Field Museum has a new addition to their website: "Pompeii: Stories from an Eruption". This website surveys the Pompeii eruption event and is also a promotion for an exhibition of the same name which will be at The Field Museum between October 22, 2005 and March 26, 2006. Details of the Vesuvius eruption phases and their impact upon the well-known cities of Pompeii and Herculaneum, but also the lesser known cities of Oplontis and Terzigno are provided. 
Field Museum ScreenshotVisit the Pompeii: Stories from an Eruption website. Labels: Volcanoes
Thursday, November 17, 2005
Galeras Volcano Forces Evacuations in Colombia
Seismic activity at Galeras Volcano in southwestern Colombia is strongly suggesting an imminent eruption. The government has issued an evacuation order for residents of the surrounding area. 
Image by USGS Read more about Galeras Volcano at the BBC Website. Labels: Volcanoes
Thursday, November 03, 2005
Global Volcanism Program Website
Smithsonian Institute's Global Volcanism Program Website is worth a long visit. It documents the Holocene eruption history of the Earth’s major volcanoes. The site is rich in images, data, maps and other information. Perhaps its best feature is the superior organization that makes research and browsing easy. 
Screenshot of the GVP WebsiteVisit the Global Volcanism Website! Labels: Volcanoes
Wednesday, October 26, 2005
Galapagos Islands Volcano - Sierra Negra
Sierra Negra Volcano, on the Galapagos Island of Isla Isabela, has been erupting since October 22. The image below shows a heavy plume of volcanic ash and steam streaming from the volcano to the southwest. Lava flows have descended the northeast side of the mountain but have not threatened people or rare species such as the giant tortises and land iguanas. 
Image by NASALabels: Volcanoes
Tuesday, August 16, 2005
Volcanic Eruption Latitude Influences Global Climate Threat
A new NASA-funded study suggests that the latitude of a volcanic eruption plays an important role in determining the impact on global climate. They used general circulation computer climate models to determine that aerosols produced by volcanoes erupting in the far north or south remain in those latitudes where they were not heated as much. In turn, the lower stratosphere did not warm greatly, so there was little influence on the arctic oscillation. On the other hand, tropical latitude eruptions usually create aerosols that spread around the globe and block heat from the sun in the lower atmosphere, cooling temperatures in areas close to the tropics. The result is a reduction in north to south temperature difference which keeps frigid air north during the winter. 
Image by NASARead more about How Latitude of a Volcanic Eruption can Influence Global Climate at the NASA website. Labels: Volcanoes
Monday, August 15, 2005
Visitors up by over 25% at Mt. St. Helens National Volcanic Monument
Visitor counts are up by more than 25% this summer at Mt. St. Helens National Volcanic Monument. Part of this can be attributed to the 25th anniversary of the 1980 eruption and part can be attributed to the opportunity to experience the low rates of seismicity, low emissions of steam and volcanic gases, and minor production of gas and ash that can be seen from the Johnson Ridge Observatory. Over 250,000 visitors are expected to observe the volcano this year. 
Image by USGSRead more at the Mt. St. Helens homepage. Labels: Volcanoes
Wednesday, June 08, 2005
Mexico: Colima Volcano Eruption
There is new eruption activity at Colima Volcano in Mexico. Colima is considered to be Mexico's most active and dangerous volcano. The latest eruption sequence began on May 24th and the strongest eruption in the past 20 years occurred on June 3rd. The images of Colima Volcano shown below are from the Earth Observatory website. Visit there to learn more about this eruption of Colima Volcano and to see the same images in greater detail.  Labels: Volcanoes
Wednesday, June 01, 2005
Geotimes Article About the Yellowstone Caldera
A very good article titled "Truth Fiction and Everything in between at Yellowstone" has been published on the Geotimes website. This article was written by one of the most credible people on this subject, Jake Lowenstern, scientist-in-charge for the Yellowstone Volcano Observatory. The goal of this article is to set the record straight on past and future eruptions at the Yellowstone Caldera. The observatory is based at Menlo Park, California. It is a partnership between Yellowstone National Park, USGS and its Volcano Hazards Program, and the University of Utah, which operates the earthquake and ground-deformation monitoring networks. Read about Volcanic Eruptions at the Yellowstone Caldera.  Labels: Volcanoes
Saturday, May 21, 2005
USGS Releases US Volcanic Threat Report
USGS has released a report on the 169 volcanoes within the United States, rating them into groups on the basis of threat. Volcanoes in the "Very High Threat" category include: Akutan, Augustine, Makushin, Redoubt, and Spurr in Alaska; Lassen, Long Valley Caldera and Shasta in California; Kilauea and Mauna Loa in Hawaii; Crater Lake, Hood, Newberry and South Sister in Oregon; and Baker, Glacier Peak, Rainier and St. Helens in Washington. The Volcanic Threat Report can be downloaded from the USGS website.  Labels: Volcanoes
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