Types of volcanism and volcanic hazards.

1. The Fiery Earth

2. • There are 4 types of volcanism on Earth
1. Shield cones
2. Cinder cones
3. Composite cones
4. Fissure Eruptions

3. • Large volcanoes with broad bases and gently
sloping sides
– Lava composition is mafic
– Few gases
– Relatively quiet eruptions
– Igneous rocks created: Basalt; some Scoria

4. Mauna Loa, Hawaii

5. Mauna Kea, Hawaii

6. • Small volcanoes with steep slopes
– Lava composition is
felsic, however
generally low silica
– Higher gas content
– Explosive eruptions
– Igneous rocks
created: Scoria

7. Lava Butte, Oregon

8. Cerro Negro, Nicaragua

9. • Tall, steep volcanoes made
of alternating layers of
hardened lava flows.
– Lava composition is felsic
– Gases vary
– Both quiet and explosive
eruptions
– Igneous rocks created:
Pumice, Obsidian, Rhyolite

10. Mount St. Helens, Washington

11. Mount Pinatubo, Phillipines

12. • Fracture or crack from which lava erupts
– Lava composition is mafic
– Few gases
– Quiet eruptions, repeated layers
– Igneous rocks created: Basalt

14. • Tiny jagged pieces of
rock and glass
– After an eruption,
wind can carry ash
far away
– Most settles on the
land around the
volcano

15. • Aa – jagged chunks of lava formed by
rapid cooling.

16. • Pahoehoe – forms
a wrinkled, ropy
texture as the
lava cools.

17. • A fast moving flow of mud, rocks, and debris
– occurs when
water from
glaciers is
released due to a
volcanic
eruption

18. • A fast-moving, dense, super-heated,
poisonous gas cloud.

19. • Large clots of lava thrown out of an erupting volcano
– while red-hot,
spin through the
air, cool, and
develop a round or
spindle shape.

20. Images
1. Ellen van den Berg, “The Skjaldbreiour Shield Volcano” September 2, 2009 via Flickr, Attribution-
NonCommercial-NoDerivs License http://farm3.staticflickr.com/2422/3903567972_aab3c8429a_z.jpg
2. Dan Dzurisin, “Overlook Vent and Mauna Loa, Predawn” June 15, 2008 via Flickr, Attribution-
NonCommercial-NoDerivs License http://farm4.staticflickr.com/3024/2582939400_e0aeeb30a2_z.jpg
3. Hector Parayuelos, “Maua Kea 1” September 5, 2009 via Flickr, Attribution-NonCommercial-
NoDerivs License http://farm8.staticflickr.com/7168/6620817281_b2a6079619_z.jpg
4. Tim Rawle, “Cinder Cones of Hale Pohaku” March 25, 2009 via Flickr, Attribution-NonCommercial-
NoDerivs License http://farm3.staticflickr.com/2436/3543949826_5540b79619_z.jpg
5. Rhiannon Boyle, “Lava Butte” August 2, 2010 via Flickr, Attribution-NonCommercial-NoDerivs
License http://farm5.staticflickr.com/4080/4880719919_7aaa7082dd_z.jpg
6. Garrett Ziegler, “Cerro Negro, Nicaragua” May 29, 2012 via Flickr, Attribution-NonCommercial-
NoDerivs License http://farm9.staticflickr.com/8025/7355197970_accf1e28df_z.jpg
7. Jessica, “Mount Fuji” November 16, 2012 via Flickr, Attribution-NonCommercial-NoDerivs License
http://farm9.staticflickr.com/8204/8230795750_7e493a8f3a_z.jpg
8. Dave Schumaker, “Mount St. Helens” August 19, 2009 via Flickr, Attribution-NonCommercial-
NoDerivs License http://farm4.staticflickr.com/3518/3844015809_40d284ab40_z.jpg

21. Images, continued
9. Storm Crypt, “Pinatubo’s Northeast Shore” August 16, 2008 via Flickr, Attribution-NonCommercial-
NoDerivs License http://farm4.staticflickr.com/3128/2927114406_0e573f4175_z.jpg?zz=1
10. Islomaniac, “New lava fountain eruption from smoldering fissure” March 2011 via Flickr, Attribution
License http://farm6.staticflickr.com/5175/5536447923_01e3470e13_o.jpg
11. Finnur Malmquist, “Eruption in Eyjafjallajokull” May 7, 2010 via Flickr, Attribution-NonCommercial-
NoDerivs License http://farm5.staticflickr.com/4070/4588825332_58d859df97_z.jpg
12. ccarlstead, “Aa Lava Flow” January 13, 2011 via Flickr, Attribution-NonCommercial-NoDerivs License
http://farm6.staticflickr.com/5171/5412138468_0c097402b8_z.jpg
13. Zack Jackson, “Lava” January 12, 2005 via Flickr, Attribution-NonCommercial-NoDerivs License
http://farm4.staticflickr.com/3078/3241111818_78c08cc901_z.jpg
14. UWI Seismic Research Centre, “Lahar flow in Plymouth” May 20, 2005 via Flickr, Attribution-
NonCommercial-NoDerivs License http://farm3.staticflickr.com/2443/3706671983_801e8f2989_z.jpg
15. gnuckx, “Italy Etna Volcano” October 27, 2008, Attribution License
http://farm4.staticflickr.com/3484/3208523096_6ba9e9c115_z.jpg
16. GabeD, “Galapagos-Isabela” December 28, 2008 via Flickr, Attribution-NonCommercial-NoDerivs
License http://farm4.staticflickr.com/3261/3203163476_5d233f099b_z.jpg?zz=1