Geography: Iceland - volcano's

Read the full article here:  Ref: http://news.bbc.co.uk/1/hi/world/europe/8623239.stm 

 

EXTRACT:

 

“Iceland is a volcanic hot spot on the Mid-Atlantic Ridge - the dividing line between the Eurasian and North American continental plates.

The country's three major volcanoes - Hekla, Katla and Grimsvotn - lie along this boundary.

Altogether there are 35 active volcanoes on and around the island.

Icelandic volcanoes have long drawn tourists from across the globe, eager to catch a glimpse of a pillar of smoke or a spectacular lava flow. But there have also been cataclysmic events.

Eruptions at the eastern volcanoes of Grimsvotn and from 1783 to 1785 Laki produced a lava flow which consumed vast swathes of land, blotted out the sun and killed a quarter of the population through poisoning or famine.

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SELECTED BIG ERUPTIONS

1783-85: Grimsvotn-Laki - lava inundated 300 sq km, sulphur dioxide and hydrogen fluoride emitted killed 9,000 people

1918: Katla eruption

1947-48: Hekla - 11-month eruption, major lava flow, 24,000 tonnes of carbon dioxide emitted

1973: Eldfell - seven-month eruption on island of Heimaey

1996: Grimsvotn erupts, causing a glacial burst (where a build-up of water under the ice of a glacier is suddenly released)

2004: Grimsvotn - eruption sends ash up to 12km into the air, some of it landing in Norway, Sweden and Finland

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Some useful info:

 

Eyjafjallajokull means "island mountain glacier"

Eyja means "islands"

Fjall means "mountain"

Jokull means "glacier"

-It's the mountain with the glacier seen from, or around, the Westman islands, off Iceland's south-western coast

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Source: http://news.bbc.co.uk/1/hi/world/europe/8623239.stm

Geology: Types of Rocks

Here is a link to a great virtual rock kit:  http://www.earthscienceeducation.com/virtual_rock_kit/index.htm

Here is a list of all unique rock types as recognized by petrologists:

1.  Igneous
2.  Metamorphic
3.  Sedimentary

Source:  http://en.wikipedia.org/wiki/List_of_rock_types
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In geology, rock or stone is a naturally occurring solid aggregate of minerals and/or mineraloids.


The Earth's outer solid layer, the lithosphere, is made of rock. In general rocks are of three types, namely, igneous, sedimentary, and metamorphic. The scientific study of rocks is called petrology, and petrology is an essential component of geology.
 
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Also looking at:

Volcanic / Magma
Plutonic
Basalt
Gneiss
Quartzite
Granite
Schist


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Link:  On the origin of early Archaean gneisses by  A. Y. Glikson - http://www.springerlink.com/content/r459kx50j0764622/

GEOGRAPHY: Volcanic craters

Today we read about a volcano that is thought to be about to erupt in Iceland.  Read about it here

I decided that I wanted to learn about volcanic craters and there are some awesome photos.

Then we looked at atolls.  If you have google earth you can search for atolls on there and its really awesome.  Try looking at Rakahanga Atoll, Cook Islands.

Click on the links for the websites we looked at and the photos.

Photo source:  http://www.global-travel.co.uk/tour9.htm