Situation Update No. 1
Posted:2011-05-22, 02:09:17 [UTC]
Ref.no.: VE-20110522-30830-ISL
Situation Update No. 1
On 2011-05-22 at 02:17:07 [UTC]
Event: Volcano Eruption
Location: Iceland Vatnajökull glacier Grímsvötn Volcano
Situation: Iceland's most active volcano has started erupting, scientists said Saturday — just over a year after another eruption on the North Atlantic island shut down European air traffic for days. Iceland's Meteorological Office confirmed that an eruption had begun at the Grimsvotn volcano, accompanied by a series of small earthquakes. Smoke could be seen rising from the volcano, which lies under the uninhabited Vatnajokull glacier in southeast Iceland. A no fly zone has been designated for 120 nautical miles (220 kilometers) in all directions from the eruption. Isavia, the company that operates and develops all airport facilities and air navigation services in Iceland, described this as standard procedure around eruptions. "The plume of smoke has reached jet flying altitude and plans have been made for planes flying through Icelandic air control space to fly southwardly tonight," said Hjordis Gudmundsdottir, the spokeswoman for Isavia. Grimsvotn last erupted in 2004. Scientists have been expecting a new eruption and have said previously that this volcano's eruption will likely be small and should not lead to the air travel chaos caused in April 2010 by ash from the Eyjafjallajokull volcano. History shows that previous eruptions in Grimsvotn have not had much influence on flight traffic — unlike the massive disruption caused last year.
Pall Einarsson, geophysicist at the University of Iceland, said last year's eruption was a rare event. "The ash in Eyjafjallajokull was persistent or unremitting and fine-grained," Einarsson said. "The ash in Grimsvotn is more coarse and not as likely to cause danger as it falls to the ground faster and doesn't stay as long in the air as in the Eyjafjallajokull eruption." A plane from the Icelandic Coast Guard carrying experts from the University of Iceland will fly over the volcano and evaluate the situation. One eyewitness, Bolli Valgardsson, said the plume rose quickly several thousand feet (meters) into the air. Sparsely populated Iceland is one of the world's most volcanically active countries and eruptions are frequent. Eruptions often cause local flooding from melting glacier ice, but rarely cause deaths. Last year's Eyjafjallajokul eruption left some 10 million air travelers stranded worldwide after winds pushed the ash cloud toward some of the world's busiest airspace and led most northern European countries to ground all planes for five days. Whether widespread disruption occurs again will depend on how long the eruption lasts, how high the ash plume rises and which way the wind blows. In November, melted glacial ice began pouring from Grimsvotn, signaling a possible eruption. That was a false alarm but scientists have been monitoring the volcano closely ever since. The volcano also erupted in 1998, 1996 and 1993. The eruptions have lasted between a day and several weeks.
Info4 Volcanic eruptions
World Map of Volcanoes, Earthquakes, Impact Craters, and Plate Tectonics | ||
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This site supports and extends a 1x1.5 m wall map available through the "Order" link [above]. |
 | | The map is designed to show Earth's most prominent features when viewed from a distance, and more detailed features upon closer inspection. The back of the map zooms in further, highlighting examples of fundamental processes, while providing text, timelines, references, and other resources to enhance understanding of this dynamic planet. The main and polar maps, above, are interactive, inviting you to make your own regional map, using whichever "layers" you choose. Data for any volcano, earthquake, or impact symbol can be found via the "Identify" tool. |
Back of Map | ||
Most new crust forms at ocean ridge crests, is carried slowly away by plate movement, and is ultimately recycled deep into the earth�causing earthquakes and volcanism along the boundaries between moving tectonic plates. Oceans are continually opening (e.g., Red Sea, Atlantic) or closing (e.g., Mediterranean). Because continental crust is thicker and less dense than thinner, younger oceanic crust, most does not sink deep enough to be recycled, and remains largely preserved on land. Consequently, most continental bedrock is far older than the oldest oceanic bedrock (see back of map). The earthquakes and volcanoes that mark plate boundaries are clearly shown on this map, as are craters made by impacts of extraterrestrial objects that punctuate Earth's history, some causing catastrophic ecological changes. Over geologic time, continuing plate movements, together with relentless erosion and redeposition of material, mask or obliterate traces of earlier plate-tectonic or impact processes, making the older chapters of Earth's 4,500-million-year history increasingly difficult to read. The recent activity shown on this map provides only a present-day snapshot of Earth's long history, helping to illustrate how its present surface came to be. Both the front and back of this map illustrate the enormous recent growth in our knowledge of planet Earth. Yet, much remains unknown, particularly about the processes operating below the ever-shifting plates and the detailed geological history during all but the most recent stage of Earth's development. | ||
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Volcano
A volcano is a mountain that opens downward to a reservoir of molten rock below the surface of the earth. Unlike most mountains, which are pushed up from below, volcanoes are built up by an accumulation of their own eruptive products. When pressure from gases within the molten rock becomes too great, an eruption occurs. Eruptions can be quiet or explosive. There may be lava flows, flattened landscapes, poisonous gases, and flying rock and ash.
Because of their intense heat, lava flows are great fire hazards. Lava flows destroy everything in their path, but most move slowly enough that people can move out of the way.
Fresh volcanic ash, made of pulverized rock, can be abrasive, acidic, gritty, gassy, and odorous. While not immediately dangerous to most adults, the acidic gas and ash can cause lung damage to small infants, to older adults, and to those suffering from severe respiratory illnesses. Volcanic ash also can damage machinery, including engines and electrical equipment. Ash accumulations mixed with water become heavy and can collapse roofs. Volcanic ash can affect people hundreds of miles away from the cone of a volcano.
Sideways directed volcanic explosions, known as "lateral blasts," can shoot large pieces of rock at very high speeds for several miles. These explosions can kill by impact, burial, or heat. They have been known to knock down entire forests.
Volcanic eruptions can be accompanied by other natural hazards, including earthquakes, mudflows and flash floods, rock falls and landslides, acid rain, fire, and (under special conditions) tsunamis.
Active volcanoes in the U.S. are found mainly in Hawaii, Alaska, and the Pacific Northwest. Active volcanoes of the Cascade Mountain Range in California, Oregon, and Washington have created problems recently. The danger area around a volcano covers approximately a 20-mile radius. Some danger may exist 100 miles or more from a volcano, leaving Montana and Wyoming at risk.
What is the history of volcanic eruptions where I live?
How can I protect myself from a volcanic eruption?
Find a Volcano by Region
Smithsonian Institution, Global Volcanism Program
| Mediterranean and W Asia | Africa and Red Sea | Middle East and Indian Ocean | New Zealand to Fiji | Melanesia and Australia | Indonesia | Philippines and SE Asia | Japan, Taiwan, Marianas | Kuril Islands | Kamchatka and Mainland Asia | Alaska | Canada and Western USA | Hawaii and Pacific Ocean | México and Central America | South America | West Indies | Iceland and Arctic Ocean | Atlantic Ocean | Antarctica |
All of the base maps in this section, for the world and volcanic regions, were generated using ER Mapper.
Citation Guidelines for this electronic version of Volcanoes of the World.
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