Situation Update No. 3
Posted:2011-05-22, 02:09:17 [UTC]
Ref.no.: VE-20110522-30830-ISL
Situation Update No. 3
On 2011-05-22 at 03:15:23 [UTC]
Event: Volcano Eruption
Location: Iceland Vatnajökull glacier Grímsvötn Volcano
Situation: A lot of ash has been falling around the Vatnajokull glacier and nearby towns this evening. It is expected to continue through the night and maybe into tomorrow, according to Icelandic Met Office geologist, Hjorleifur Sveinbjornsson. The ash is much coarser than that which came from Eyjafjallajokull last year. Sveinbjornsson told mbl.is that there has been little change in the eruption since it began and that ash is falling on the towns of Kirkjubaerklaustur and Hofn i Hornafirdi — as well as nearby farms. He added that the volcano is a basalt eruption and that it is a good thing that the ash is less fine than last year; which will prevent it from spreading so far. The eruption seems to be taking place very near to the site of the 2004 volcano. Sveinbjornsson says that there was very little warning of an eruption today: no warning at all at 17.00 as he was preparing to go home from his shift. At 17.30 it was clear that something was happening; and then earthquakes at 18.00 confirmed suspicions. Residents of local towns and farms reported visual confirmation of the eruption at 19.00. It seems the lava did not have much ice to melt through, as the ash cloud was very quick to form. The sizeable ash cloud can be seen from far and wide — and has even been seen from Reykjavik. Grimsvotn is in the Vatnajokull National park, which is the biggest national park in Europe. The famous Jokulsarlon glacial lagoon is also in the park and is being affected by the ash cloud. Mila provides a free webcam of Jokulsarlon here. At the time of writing the camera was showing a completely black screen — despite the fact that it no longer gets completely dark at night time at this time of year.
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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