Aim-To be able to identify the main features of a volcano and its eruption.
Case study-Mt St Helens, USA, 1980
Key words:
Volcano ( Just one)
Volcanoes ( more than one)
A volcano can be:
Active – Is erupting or has erupted recently.
Dormant – Asleep: has not erupted recently.
Extinct – Dead and will not erupt again.
Mount St Helens volcano is located in the sparsely populated Cascade Mountains in north – west USA.
Composite, or stratovolcanoes also produce explosive eruptions . Composite volcanoes form from alternating eruptions dominated by pyroclastics or lava. As a result, composite volcanoes display layers of these alternating flows. Composite volcanoes are among the tallest volcanoes on earth, with Mt. Fuji, Mt. St. Helens, and Mt. Kilimanjaro being examples. Composite volcanoes are often associated with convergent plate boundaries where subduction is occurring.
The eruption was caused because the plate Juan de Fuca dived under the North American plate causing friction. The friction changed the destroyed oceanic crust into magma. Over time the magma built up and the pressure from that made the volcano erupt.
The heat of the volcano made the snow at the top of mount St Helens melt. That made larhar (a wave of water), rushing towards the town at the bottom of the volcano. After that the ash, pyroclastic flows and gases descended down the sides of the volcano at up to 100 MPH. That killed 63 people and lots of live stock was lost. All the vegetation was flatterned and the roads were flooded. At Toutle the railway bridge got washed away. Spirit lake filled to a depth of 60m. Sadly, many fish died.
moburto12's Blog 
What a great location descriptor- do you remember what sparsely means? How might that have helped reduce the effects of the eruption?
“The eruption was caused because the plate Juan de Fuca dived under the North American plate causing friction”- what do we call this zone?
Spirit lake- should be a capital L- place name.
More images with captions would have illustrated the effects more; such as the 250km2 of trees flattened or the depth of ash that fell in the fallout zone.
I thought you showed me a cut-away diagram of the JDF/NAP boundary but I don’t see it in your blog?