Chapter 4 -Volcanism & Extrusive Rocks
Photo Credit: S. Young
Effects on Humans
• The Growth of Hawaii• Geothermal Energy• Effect on Climate• Volcanic Catastrophes• Eruptive Violence and Physical Characteristics of
Lava
Cascades Volcanoes
Mt. St. Helen’s Eruption Sequence
Gary Rosenquist Photo Sequence - Mt. St. Helen’s, May 18, 1980
~8:27 PDT8:32:47.0 PDT8:32:49.2 PDT8:32:53.3 PDT8:33:03.7 PDT8:33:18.8 PDT
Mt. St. Helen’s Animation
Mt. St. Helen’s Plinian Eruption Column - May 18, 1980
From: USGS http://vulcan.wr.usgs.gov/
Mt. St. Helen’sMay 18, 1980 Devastation
Post May 18, 1980 Crater and Resurgent Dome
From: USGS http://vulcan.wr.usgs.gov/
Caldera Collapse
Crater lake - Wizard Island - 5 kBP Eruption Mt. MazamaCrater lake, Wizard Island, OR8 kBP Eruption Mt. Mazama
From: http://www.igoweb.org/~wms/personal/photos/2000/craterLake/
Pyroclastic Flows
St. Pierre Devastation, Mt. Pelee, Martinque, May 8, 1902
Extrusive Rocks and Gases
• Scientific Investigation of Volcanism• Gases
Extrusive Rocks
Volcanic Textures Table
Obsidian Hand Specimen
Andesite Hand Specimen
Andesite Photomicrograph
Vesicular Basalt
Pumice
Volcanic Bombs
Volcanic Tuff Photomicrograph
Types of Volcanoes
• Shield Volcanoes• Cinder Cones• Composite Volcanoes• Volcanic Domes
Basic Volcano Types
Karymsky Volcano, Kamchatka, Russia
Shield Volcano
Basaltic Fire Fountaining and Lava Flows
Summit of Mauna Loa
Pahoehoe Lava Flow
Aa Lava Flow
Spatter Cone
Olympus Mons, Mars
Volcanic Eruption, Io