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Big Bunny
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« Reply #60 on Apr 26, 2010, 9:02pm » | |
Santiaguito Volcano showers sand and ash over Guatemala
* From: AFP
* April 27, 2010 11:25AM
THE Santiaguito volcano showered sand and ash over a large area of western Guatemala in an "unusual" and "violent" display, the national seismological institute said.
The institute said winds were carrying the ash in a northeasterly direction from the 2500 metre high volcano in the province of Quetzaltenango, 206 kilometres west of the capital.
The ash plume spread across six provinces, raising fears of damage to crops, the institute said while classes were suspended at schools in three provinces.
Santiaguito's worst eruption occurred in 1929 when 2500 people were killed.
http://www.news.com.au/breaking-news/san....-12258587 33932
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"All truth passes through three stages. First, it is ridiculed, second it is violently opposed, and third, it is accepted as self-evident."
Arthur Schopenhauer, Philosopher, 1788-1860
"In the final analysis, our most basic common link is that we all inhabit this small planet, breathe the same air, and we all cherish our children’s future."
John F. Kennedy |
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Big Bunny
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| | Re: Earthquakes III
« Reply #61 on Apr 28, 2010, 7:09pm » | |
Scientists Study 'Glaciovolcanoes,' Mountains of Fire and Ice, in Iceland, British Columbia, US
![[image]](http://img687.imageshack.us/img687/7156/100426092807large954201.jpg "[image]")
The eruption in Iceland after it penetrated Eyjafjallajökull's icecap; new ash covers the glacier. (Credit: Marco Fulle)
ScienceDaily (Apr. 23, 2010) — Glaciovolcanoes, they're called, these rumbling mountains where the orange-red fire of magma meets the frozen blue of glaciers.
Iceland's Eyjafjallajökull volcano, which erupted recently, is but one of these volcanoes. Others, such as Katla, Hekla and Askja in Iceland; Edziza in British Columbia, Canada; and Mount Rainier and Mount Redoubt in the U.S., are also glaciovolcanoes: volcanoes covered by ice.
"When an ice-covered volcano erupts, the interplay among molten magma, ice and meltwater can have catastrophic results," says Sonia Esperanca, program director in the National Science Foundation (NSF)'s Division of Earth Sciences, which funds research on glaciovolcanoes.
In Iceland last week, scientists were well prepared for the floods, called "jökulhlaups," that can happen after a glaciovolcano blows and melts its glacial covering. The floods were followed by tons of ash ejected into the atmosphere.
Most of the rest of the world, however, was unaware that an eruption from a small, northern island in the middle of the Atlantic Ocean could freeze air transportation and stop global commerce in its tracks.
That, say NSF-funded scientists Ben Edwards at Dickinson College and Ian Skilling at the University of Pittsburgh, is the nature of glaciovolcanoes.
Understanding volcano-ice interactions occupies much of Edwards' and Skilling's daily lives.
They're working at Mt. Edziza in British Columbia, Canada, and in Iceland to find out how glaciovolcanic deposits--rock fragments strewn for miles after an ice-covered volcano erupts--are formed.
Volcano-ice interaction presents unique types of hazards, say the geologists, but what's left behind after an eruption can also serve as a window into our geologic past.
Studies of glaciovolcanoes' deposits are helping scientists get a better handle on Earth's long-term climate cycles. The volcanic shards are "proxies" for climates of the past.
A key to using these rocks as proxies is the ability to correctly interpret fragmentation of lava and other textural and chemical features. From these, scientists estimate snow and ice thicknesses before and during a glaciovolcano's eruption. The quantity of ash and flowing lava changes as the eruption progresses, until magma stops being formed.
Glaciovolcanic deposits are identifiable long after an eruption ends. Pillow lava, for example, which usually forms on the ocean floor, is sometimes found high atop mountains in British Columbia and Iceland, and in the Antarctic.
These round tubes of fossilized lava, coated with shiny black volcanic glass, are indications of volcanoes that once erupted beneath ice or water.
By noting the elevation of pillow lavas on mountains or high ridges, geologists can better determine the thickness of surrounding ice.
"Pillow lavas might well be forming right now in the ice-bound caverns on top of Eyjafjallajökull," says Edwards. "By analyzing the gas content dissolved in pillow lavas' glass, we can also estimate the thickness of the overlying ice at the time of their formation."
When hot lava melts ice quickly, water can mix with magma, flash to steam, and produce powerful explosions of fine volcanic ash, according to Edwards.
"These fine particles can be carried much higher into the atmosphere than ash from similar 'dry' eruptions," he says.
When superheated fragments of liquid magma hit cold air, they freeze into billions and billions of particles, driven into the atmosphere by the power of the volcano's eruption.
"Although studies of glaciovolcanism are currently focused on longer-term questions of climate change, the research is helping scientists understand all active and dormant ice-covered volcanoes, including many in North America," says Esperanca.
Several volcanoes in the Cascades, such as Mount Rainier, and volcanoes in Alaska, like the recently active Mount Redoubt, have significant ice cover.
Research on the links between these volcanoes and their ice-covered surfaces is giving scientists and emergency planners critical information.
"We need more studies of present and old eruptions to be prepared to respond to a volcano-ice crisis in North America--or elsewhere around the globe," says Esperanca.
While many geologists are using Iceland as an important way to inform the public about possible dangers from volcanoes, glaciovolcanologists are chomping at their rock hammers--and ice chisels.
They're waiting for Eyjafjallajökull to take a rest. Then they can creep ever closer, eventually getting a look at newly formed glaciovolcanic deposits.
To Edwards and Skilling, the eruption of Eyjafjallajökull shows how complex the dance of a volcano and a glacier can be.
http://www.sciencedaily.com/releases/2010/04/100426092807.htm
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"All truth passes through three stages. First, it is ridiculed, second it is violently opposed, and third, it is accepted as self-evident."
Arthur Schopenhauer, Philosopher, 1788-1860
"In the final analysis, our most basic common link is that we all inhabit this small planet, breathe the same air, and we all cherish our children’s future."
John F. Kennedy |
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Big Bunny
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| | Re: Earthquakes III
« Reply #62 on May 9, 2010, 3:49am » | |
Latest significant seismic activity:
DATE LAT LON MAG DEPTH REGION
09-MAY-2010 05:59:44 3.73 96.08 7.2 61.4 NORTHERN SUMATERA, INDONESIA
07-MAY-2010 17:58:36 9.38 93.03 4.8 70.2 NICOBAR ISLANDS, INDIA
07-MAY-2010 09:23:53 13.63 92.63 4.6 35.0 ANDAMAN ISLANDS, INDIA
06-MAY-2010 09:13:09 -3.95 100.96 5.4 31.5 SOUTHERN SUMATERA, INDONESIA
06-MAY-2010 06:51:15 -4.48 100.93 4.7 15.2 SOUTHWEST OF SUMATERA, INDONESIA
06-MAY-2010 06:14:48 -4.38 100.89 4.6 13.4 SOUTHWEST OF SUMATERA, INDONESIA
06-MAY-2010 05:40:32 2.05 96.66 4.6 10.1 NORTHERN SUMATERA, INDONESIA
05-MAY-2010 16:29:02 -4.08 101.07 6.5 18.1 SOUTHERN SUMATERA, INDONESIA
http://www.iris.edu/seismon/
|
"All truth passes through three stages. First, it is ridiculed, second it is violently opposed, and third, it is accepted as self-evident."
Arthur Schopenhauer, Philosopher, 1788-1860
"In the final analysis, our most basic common link is that we all inhabit this small planet, breathe the same air, and we all cherish our children’s future."
John F. Kennedy |
|
Big Bunny
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| | Re: Earthquakes III
« Reply #63 on May 23, 2010, 10:33pm » | |
Icelandic volcano now appears to be dormant, say scientists
It's too early to say this is over, but at the moment Eyjafjallajökull is quiet, said official
* David Batty
* guardian.co.uk, Sunday 23 May 2010 20.20 BST
![[image]](http://img245.imageshack.us/img245/8895/aplumeofashrisesfrom006.jpg "[image]")
Eyjafjallajokull last erupted from 1821 to 1823; vulcanologists say this is the only guide to how long the current eruptions will continue. Photograph: Brynjar Gauti/AP
There has been a marked drop in the volcanic activity in Iceland that has disrupted flights across Europe for more than a month, and observers say the volcano "appears to be dormant".
Icelandic scientists said that their latest readings at Eyjafjallajökull found little eruption activity, although they warned it was too early to say it was completely over.
Heat camera footage from early indicated that the temperature inside the crater had dropped to 100C, meaning the volcano is now producing steam rather than magma and ash, according to the status report issued by the Icelandic Met Office and Institute of Earth Sciences, University of Iceland.
Tremors inside the volcano are also decreasing and approaching the level before the eruption.
"The eruption activity is minimal and therefore no significant ashfall is expected," said the report, published last night. "The eruption seems to be dormant today. There is still a considerable amount of steam coming from the crater, but no ash can be seen in it."
The observers continue their monitoring and will issue another ashfall forecast if necessary. "What I can confirm is that the activity of the crater has stopped," said vulcanologist Magnus Gudmundsson. "No magma is coming up."
Civil Protection Agency official Iris Marelsdottir commented: "Now we can only wait and see. It's too early to say this is over, but at the moment it is quiet."
Eyjafjallajökull erupted on 14 April for the first time in two centuries, leading to a six-day shutdown of UK airspace under international aviation rules which banned all flying in areas affected by the ash cloud. Most northern European countries similarly shut their airspace over the period 15-20 April, grounding an estimated 10 million travelers worldwide and costing the airline industry £2.1bn.
Most of the cost has been incurred by Europe's airlines, with BA losing up to £20m a day.
The European airline sector was already expected to lose $2.2bn this year, and some analysts have warned that the ash cloud could drive weaker airlines out of business.
Thousands of Britons were stranded overseas during the flight ban, with some taking days to return by rail, road and sea.
The last eruption in Iceland in November 2004 from the Grímsvötn volcano caused an ash plume over Scandinavia and caused short-term disruption of air traffic into Iceland.
Scientists have warned that there is still a significant chance that the much larger Katla volcano, to the east of Eyjafjallajökull, will erupt; the previous three times Eyjafjallajökull erupted, Katla did also. And on average, Katla has erupted every 60 years and has not done so significantly since 1918.
http://www.guardian.co.uk/world/2010/may....uption-activity
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"All truth passes through three stages. First, it is ridiculed, second it is violently opposed, and third, it is accepted as self-evident."
Arthur Schopenhauer, Philosopher, 1788-1860
"In the final analysis, our most basic common link is that we all inhabit this small planet, breathe the same air, and we all cherish our children’s future."
John F. Kennedy |
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Big Bunny
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| | Re: Earthquakes III
« Reply #64 on May 26, 2010, 11:16am » | |
Latest significant seismic activity:
DATE LAT LON MAG DEPTH REGION
24-MAY-2010 16:18:29 -8.07 -71.57 6.5 578.5 WESTERN BRAZIL
23-MAY-2010 22:46:53 -13.90 -74.33 6.1 109.6 CENTRAL PERU
22-MAY-2010 05:48:11 -13.44 -69.87 4.4 599.8 PERU-BOLIVIA BORDER REGION
20-MAY-2010 17:38:51 -1.94 -78.31 4.5 128.4 ECUADOR
19-MAY-2010 04:15:42 -5.07 -77.56 6.0 125.6 NORTHERN PERU
http://www.iris.edu/seismon/
|
"All truth passes through three stages. First, it is ridiculed, second it is violently opposed, and third, it is accepted as self-evident."
Arthur Schopenhauer, Philosopher, 1788-1860
"In the final analysis, our most basic common link is that we all inhabit this small planet, breathe the same air, and we all cherish our children’s future."
John F. Kennedy |
|
Big Bunny
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| | Re: Earthquakes III
« Reply #65 on May 26, 2010, 11:18am » | |
Latest significant seismic activity:
DATE LAT LON MAG DEPTH REGION
25-MAY-2010 10:09:06 35.35 -35.93 6.0 10.0 NORTHERN MID-ATLANTIC RIDGE
http://www.iris.edu/seismon/
|
"All truth passes through three stages. First, it is ridiculed, second it is violently opposed, and third, it is accepted as self-evident."
Arthur Schopenhauer, Philosopher, 1788-1860
"In the final analysis, our most basic common link is that we all inhabit this small planet, breathe the same air, and we all cherish our children’s future."
John F. Kennedy |
|
Big Bunny
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| | Re: Earthquakes III
« Reply #66 on May 26, 2010, 11:20am » | |
Latest significant seismic activity:
DATE LAT LON MAG DEPTH REGION
26-MAY-2010 11:51:23 25.72 130.13 5.0 9.9 SOUTHEAST OF RYUKYU ISLANDS
26-MAY-2010 08:53:06 25.77 130.03 6.4 4.2 SOUTHEAST OF RYUKYU ISLANDS
20-MAY-2010 22:02:59 25.84 128.54 4.8 9.2 RYUKYU ISLANDS
17-MAY-2010 07:59:02 28.74 128.89 4.6 44.0 RYUKYU ISLANDS
16-MAY-2010 12:35:50 28.82 128.53 5.2 42.0 RYUKYU ISLANDS
16-MAY-2010 11:26:16 28.75 128.69 4.7 36.0 RYUKYU ISLANDS
13-MAY-2010 11:01:14 33.35 131.49 4.9 93.0 KYUSHU, JAPAN
http://www.iris.edu/seismon/
|
"All truth passes through three stages. First, it is ridiculed, second it is violently opposed, and third, it is accepted as self-evident."
Arthur Schopenhauer, Philosopher, 1788-1860
"In the final analysis, our most basic common link is that we all inhabit this small planet, breathe the same air, and we all cherish our children’s future."
John F. Kennedy |
|
Big Bunny
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| | Re: Earthquakes III
« Reply #67 on May 27, 2010, 2:16pm » | |
Latest significant seismic activity:
DATE LAT LON MAG DEPTH REGION
27-MAY-2010 20:48:00 -13.64 166.71 6.4 32.2 VANUATU ISLANDS
27-MAY-2010 17:45:29 -13.66 166.78 5.2 35.0 VANUATU ISLANDS
27-MAY-2010 17:24:23 -13.89 166.64 5.7 35.0 VANUATU ISLANDS
27-MAY-2010 17:14:48 -13.71 166.51 7.2 36.1 VANUATU ISLANDS
http://www.iris.edu/seismon/
|
"All truth passes through three stages. First, it is ridiculed, second it is violently opposed, and third, it is accepted as self-evident."
Arthur Schopenhauer, Philosopher, 1788-1860
"In the final analysis, our most basic common link is that we all inhabit this small planet, breathe the same air, and we all cherish our children’s future."
John F. Kennedy |
|
Big Bunny
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| | Re: Earthquakes III
« Reply #68 on May 28, 2010, 8:03am » | |
Electric Ash Found in Eyjafjallajokull's Plume, Say UK Researchers
![[image]](http://img266.imageshack.us/img266/6571/100527013219large150465.jpg "[image]")
Eruption of the volcano Eyjafjallajokull in South Iceland. (Credit: iStockphoto/Jochen Scheffl)
ScienceDaily (May 27, 2010) — In the first peer-reviewed scientific paper to be published about the Icelandic volcano since its eruption in April 2010, UK researchers write that the ash plume which hovered over Scotland carried a significant and self-renewing electric charge.
The volcano-chasing researchers argue this adds a further dimension to understanding the detailed nature of volcanic plumes and their effects on air travel.
The paper, to be published May 27 in IOP Publishing's Environmental Research Letters, is published as the UK continues to face the possibility of further flight disruption from future volcanic activity.
Shortly after the volcano's active eruption phase began in mid-April, the Met Office contacted Joseph Ulanowski from the Science and Technology Research Institute at the University of Hertfordshire, who last year, together with Giles Harrison from the Department of Meteorology at the University of Reading, had developed a specialist weather balloon which could assess the location and composition of the volcanic ash clouds.
Their balloons, originally designed and used to study the properties of desert dust clouds, are able to assess not only the size of atmospheric particles but also the electric charge present.
Measurements made last year with the balloons in Kuwait and off the west coast of Africa showed clearly that desert dust could become strongly electrified aloft. Charging modifies particle behaviour, such as how effectively particles grow and are removed by rain.
A hastily scrambled team travelled to a site near Stranraer in Scotland where a balloon was launched, detecting a layer of volcanic ash 4km aloft, about 600m thick, with very abrupt upper and lower edges.
From their measurements, the researchers conclude that neither energy from the volcanic source -- more than 1200 kilometres away -- nor weather conditions could have been responsible for the position of the charge found by the balloon.
The presence of charge deep inside the plume, rather than on its upper and lower edges, contradicts expectations from models assuming solely weather-induced charging of layer clouds.
Giles Harrison said, "Detailed volcanic plume properties, such as the particle size, concentration and charge found by our weather balloon are important in predicting the impact on aircraft."
Journal Reference:
1. R G Harrison, K a Nicoll, Z Ulanowski, T A Mather. Self-charging of the Eyjafjallajökull volcanic ash plume. Environmental Research Letters, 2010; DOI: 10.1088/1748-9326/5/2/024004
http://www.sciencedaily.com/releases/2010/05/100527013219.htm
|
"All truth passes through three stages. First, it is ridiculed, second it is violently opposed, and third, it is accepted as self-evident."
Arthur Schopenhauer, Philosopher, 1788-1860
"In the final analysis, our most basic common link is that we all inhabit this small planet, breathe the same air, and we all cherish our children’s future."
John F. Kennedy |
|
Big Bunny
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| | Re: Earthquakes III
« Reply #69 on May 30, 2010, 1:29am » | |
Ecuador volcanic eruption calms
Posted 9 hours 22 minutes ago
![[image]](http://img96.imageshack.us/img96/5332/47952151009403599133697.jpg "[image]")
An eruption by Ecuador's Throat of Fire volcano abated on Saturday, leading authorities to start allowing 2,500 evacuees to return home and announce plans to reopen a major airport later in the day.
"The volcano has lowered its intensity... there is less ash," said Sandra Vaca, an official at Ecuador's Geophysical Institute.
Residents of rural villages close to 5,020-metre Tungurahua were evacuated on Friday and the airport in the coastal city of Guayaquil was closed.
Ash particles can cause serious damage if sucked into plane engines. An Icelandic volcano caused widespread disruption and major losses for airlines after flights were grounded for days in Europe in mid-April.
Some of the evacuated villagers began to return to their homes on Saturday and the airport was due to reopen in the afternoon after the runway was swept of volcanic ash.
Tungurahua, which means Throat of Fire in the local Quechua language, has been classified as active since 1999 and produced a strong eruption in 2008.
It is one of Ecuador's eight active volcanoes.
http://www.abc.net.au/news/stories/2010/05/30/2913048.htm?section=world
|
"All truth passes through three stages. First, it is ridiculed, second it is violently opposed, and third, it is accepted as self-evident."
Arthur Schopenhauer, Philosopher, 1788-1860
"In the final analysis, our most basic common link is that we all inhabit this small planet, breathe the same air, and we all cherish our children’s future."
John F. Kennedy |
|
Big Bunny
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| | Re: Earthquakes III
« Reply #70 on May 30, 2010, 9:46pm » | |
Deep Subduction of the Indian Continental Crust Beneath Asia
![[image]](http://img291.imageshack.us/img291/3809/100528101552large342510.jpg "[image]")
The map shows the location of the study area in the Himalayas. Inset: A schematic shows the Indian plate subducting beneath the Asian plate. (Credit: NOC)
ScienceDaily (May 29, 2010) — Geological investigations in the Himalayas have revealed evidence that when India and Asia collided some 90 million years ago, the continental crust of the Indian tectonic plate was forced down under the Asian plate, sinking down into the Earth's mantle to a depth of at least 200 km kilometres.
"The subduction of continental crust to this depth has never been reported in the Himalayas and is also extremely rare in the rest of world," said Dr Anju Pandey of the National Oceanography Centre in Southampton, who led the research.
Pandey and her colleagues used sophisticated analytical techniques to demonstrate the occurrence of relict majorite, a variety of mineral garnet, in rocks collected from the Himalayas.
Majorite is stable only under ultra-high pressure conditions, meaning that they must have been formed very deep down in the Earth's crust, before the subducted material was exhumed millions of years later.
"Our findings are significant because researchers have disagreed about the depth of subduction of the Indian plate beneath Asia," said Pandey.
In fact, the previous depth estimates conflicted with estimates based on computer models. The new results suggest that the leading edge of the Indian plate sank to a depth around double that of previous estimates.
"Our results are backed up by computer modelling and will radically improve our understanding of the subduction of the Indian continental crust beneath the Himalayas," said Pandey.
The new discovery is also set to modify several fundamental parameters of Himalayan tectonics, such as the rate of Himalayan uplift, angle, and subduction of the Indian plate.
The new research findings were published this month in the journal Geology.
The study was supported by the UK's Natural Environment research Council.
The researchers are Anju Pandey and Andy Milton of the National Oceanography Centre, Southampton, Mary Leech of San Francisco State university), and Preeti Singh and Pramod Verma of the University of Delhi.
Journal Reference:
1. A. Pandey, M. Leech, A. Milton, P. Singh, P. K. Verma. Evidence of former majoritic garnet in Himalayan eclogite points to 200-km-deep subduction of Indian continental crust. Geology, 2010; 38 (5): 399 DOI: 10.1130/G30584.1
http://www.sciencedaily.com/releases/2010/05/100528101552.htm
|
"All truth passes through three stages. First, it is ridiculed, second it is violently opposed, and third, it is accepted as self-evident."
Arthur Schopenhauer, Philosopher, 1788-1860
"In the final analysis, our most basic common link is that we all inhabit this small planet, breathe the same air, and we all cherish our children’s future."
John F. Kennedy |
|
Big Bunny
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| | Re: Earthquakes III
« Reply #71 on May 30, 2010, 10:05pm » | |
In Deserts, Which Dunes Are the Most Stable?
![[image]](http://img163.imageshack.us/img163/8338/1005280818174948882.jpg "[image]")
Longitudinal dunes reproduced in the laboratory. These structures are characteristically centimeter-sized. (Credit: Laboratoire de Matière et Systèmes Complexes (CNRS/Université Paris-Diderot-Paris7))
ScienceDaily (May 28, 2010) — By modeling a desert where the wind blows in two directions, researchers from CNRS and Université Paris Diderot-Paris7 have succeeded in observing and highlighting, for the very first time, the formation process and long-term evolution of two types of very large sand dunes: transverse dunes and longitudinal dunes. They have demonstrated that longitudinal dunes and barchans -- croissant-shaped dunes formed in a unidirectional wind regime -- are the most stable over time. Their results should provide a better understanding of how dunes and deserts evolve on Earth and also help to deduce important information concerning wind regimes on Titan or Mars, for example.
This work, carried out in collaboration with a PhD student from the Laboratoire d'Etudes Spatiales et d'Instrumentation en Astrophysique (CNRS / Observatoire de Paris / UPMC / Université Paris Diderot-Paris7), will be published in the June 2010 issue of the journal Geology.
To study the formation and the stability of sand dunes, Stéphane Douady's team at the Laboratoire de Matière et Systèmes Complexes (CNRS / Université Paris Diderot-Paris7) has designed an ingenious device that reproduces, in miniature scale in the laboratory, the much larger dunes found in deserts. Their experimental model is made of glass beads set in motion by water in the same way as grains of sand are moved by winds. The advantages are that the resulting dunes formed of glass beads are small (a few centimeters) and build up rapidly under water. The resulting shapes are similar to wind-generated dunes, which has enabled researchers to study in detail the mechanisms involved in their formation.
Previous work carried out by the same team has focused on the dynamics of one type of dune: the barchan, which is formed when the wind regime is unidirectional (which is the case, for example, in the south Morocco desert). These croissant-shaped dunes are slowly moved by wind force. They are now well known and correspond to a relatively simple situation. Therefore, the researchers set about recreating, in the laboratory, more complex dunes that are formed under conditions where the wind blows alternatively in two directions. In real deserts, such conditions give rise to two types of dunes: transverse dunes, in other words aligned perpendicularly to the dominant wind direction, or instead longitudinal dunes (which lie parallel to the dominant wind direction). Their formation process and long-term evolution had never previously been reproduced and monitored: such dunes are very large, measuring several hundreds of meters or even several kilometers, and their morphological evolution is thus very slow.
Thanks to the experimental device they have developed, the team of scientists not only confirmed that these two types of dunes are indeed formed under bimodal wind regimes but also highlighted some major differences between them. On the one hand, transverse dunes are formed when the two wind directions are quite similar, whereas longitudinal dunes occur when the two directions are much further apart (the angle between the two wind directions exceeds 90°). In addition, providing there is no sizeable supply of sand, longitudinal dunes remain stable over time whereas transversal dunes, taken in isolation, always end up breaking down into several small barchan-type dunes. Consequently, the most stable dunes over time are barchans and longitudinal dunes (with no external sand supply).
These results provide essential insights into our understanding of how deserts form and evolve and the manner in which winds circulate on Earth. They could also help to determine wind patterns on other planets or satellites (Titan or Mars, for example). This model will enable planetologists to check whether the winds generated by their experimental models correspond to the actual shape of dunes observed by satellite.
Journal Reference:
1. E. Reffet, S. Courrech du Pont, P. Hersen, S. Douady. Formation and stability of transverse and longitudinal sand dunes. Geology, 2010; 38 (6): 491 DOI: 10.1130/G30894.1
http://www.sciencedaily.com/releases/2010/05/100528081817.htm
|
"All truth passes through three stages. First, it is ridiculed, second it is violently opposed, and third, it is accepted as self-evident."
Arthur Schopenhauer, Philosopher, 1788-1860
"In the final analysis, our most basic common link is that we all inhabit this small planet, breathe the same air, and we all cherish our children’s future."
John F. Kennedy |
|
Big Bunny
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| | Re: Earthquakes III
« Reply #72 on May 31, 2010, 3:15am » | |
Ash cloud threatens Pacific flights
Posted 37 minutes ago
A giant plume of volcanic ash is disrupting flights in the Pacific and threatening villagers in Vanuatu, echoing similar problems that caused chaos across Europe.
Forecasters in New Zealand said the cloud, spewing from Vanuatu's Mount Yasur volcano, was about 1,800 metres high and covered an area of about 341 square kilometres.
Tourists have been urged to stay away from the volcano on Tanna island, which has disrupted domestic flights in neighbouring New Caledonia.
Peter Korisa, of the National Disaster Management Office, who is on Tanna to assess the situation, says lava and hot rocks have been spewing from the volcano and ash was raining down on nearby villages.
"There are 6,000 people in the villages around the volcano, we're not moving them out yet," Mr Korisa said.
"All tourists and tourist operators have been asked to not access the volcano. The access is restricted."
Tristan Oakley, an aviation forecaster with New Zealand's Meteorological Service, says authorities have issued an advisory and it was up to airlines to avoid the affected area or cancel flights if necessary.
The plume has forced New Caledonia's AirCal to cancel two internal flights and delay another, although disruption remains tiny compared to the havoc seen in Europe - including a week-long shutdown in the continent's north in April.
Air Vanuatu local supervisor David Dick says flights are still running between the South Pacific country's capital, Port Vila, and Tanna island, while tourism officials also said the industry was unaffected.
However the Australian Government has issued a travel advisory, saying visitors were now barred from the volcano.
"Public access to the volcano is now strictly prohibited and people living in the risk zone should move to safer areas," the advisory said.
Vanuatu, which sits on the so-called Pacific Ring of Fire known for its seismic and volcanic activity, was rocked by a 7.2-magnitude earthquake on Friday, prompting a brief tsunami warning.
The archipelago, which lies between Australia and Fiji and north of New Zealand, was hit by three major quakes in October.
http://www.abc.net.au/news/stories/2010/05/31/2914333.htm?section=justin
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"All truth passes through three stages. First, it is ridiculed, second it is violently opposed, and third, it is accepted as self-evident."
Arthur Schopenhauer, Philosopher, 1788-1860
"In the final analysis, our most basic common link is that we all inhabit this small planet, breathe the same air, and we all cherish our children’s future."
John F. Kennedy |
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Big Bunny
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Posts: 50,825
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| | Re: Earthquakes III
« Reply #73 on Jun 2, 2010, 9:30am » | |
Latest significant seismic activity:
DATE LAT LON MAG DEPTH REGION
02-JUN-2010 01:01:48 4.31 126.88 5.1 45.5 TALAUD ISLANDS, INDONESIA
31-MAY-2010 13:40:05 6.87 123.96 4.7 49.2 MINDANAO, PHILIPPINE ISLANDS
31-MAY-2010 10:16:02 6.92 124.00 6.0 33.0 MINDANAO, PHILIPPINE ISLANDS
http://www.iris.edu/seismon/
|
"All truth passes through three stages. First, it is ridiculed, second it is violently opposed, and third, it is accepted as self-evident."
Arthur Schopenhauer, Philosopher, 1788-1860
"In the final analysis, our most basic common link is that we all inhabit this small planet, breathe the same air, and we all cherish our children’s future."
John F. Kennedy |
|
Big Bunny
Admin
member is offline
Joined: Apr 2003
Gender: Male
Posts: 50,825
Location: Sydney, Australia
| | Re: Earthquakes III
« Reply #74 on Jun 2, 2010, 9:31am » | |
Latest significant seismic activity:
DATE LAT LON MAG DEPTH REGION
31-MAY-2010 19:51:48 11.12 93.70 6.4 127.7 ANDAMAN ISLANDS, INDIA
http://www.iris.edu/seismon/
|
"All truth passes through three stages. First, it is ridiculed, second it is violently opposed, and third, it is accepted as self-evident."
Arthur Schopenhauer, Philosopher, 1788-1860
"In the final analysis, our most basic common link is that we all inhabit this small planet, breathe the same air, and we all cherish our children’s future."
John F. Kennedy |
| |
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