Lesson 8-What is vulcanicity? Flashcards
1
Q
Basaltic lavas
A
- Low silica content
- 1160 temp
- Low viscosity
- Low aggressive eruptions
- Frequent
- Shield volcanoes
2
Q
Andesitic/Rhyolitic lavas
A
- High silica comntent
- 900 temp
- High viscosity
- Violent eruptions
- Infrequent
- Composite
3
Q
VEI
A
- A logrythmic measurement of the magnitude of a volcanic eruption
4
Q
Contrast between Hawaiian eruptions and Plinian eruptions
A
- Hawaiian erupts frequently wheres Plinian doesnt
- Hawiian less than 0.00001 km but Plinian was less than 1km
- Hawaiin is effusive and Plinian is paroxymal
5
Q
VEI evaluation
A
+Preperation-prevents damage and injuries
-Large range of size between volcanoes
6
Q
Strato volcanoe
A
- Explosive
- Composite-steep sided
-contain complex networks of lava flows
-could be pyroclastic flow
-Mt Fuji,St Helens
7
Q
Cilinder Cone volcano
A
- Explosive
- Layers of fine ash
-side vents/single volcanoes
-Smith Volcano,Philipines
8
Q
Caldera volcano
A
- Explosive
- Large Pillian eruptions that send ash into stratosphere
- Crater lake in Oregon
9
Q
Acid Dome volcano
A
- Explosive
- Ejects acid lava, violent due to the explosive pressures building up in the magma
- Krakatoa in Indonesia
10
Q
Shield vocano
A
- Effusive
-gently sloping sides that are formed by highly fluid lava thats usually basaltic that can flow on the surface for long distances
-Mauana Loa, Hawaii
11
Q
Fissure
A
- Effusive
- Erupts from linear structure on earths surface
- Produces lava flows that travel great distances or even pyroclastic flows and gases
- Siberian Traps