glg 101 - physical geology bob leighty volcanoes
TRANSCRIPT
GLG 101 - Physical GeologyGLG 101 - Physical Geology Bob LeightyBob Leighty
VolcanoesVolcanoes
These lecture notes are very similar to the ones I use in my traditional classes. You’ll find they are loaded with imagery and streamlined text that highlight the most essential terms and concepts. The notes provide a framework for learning and, by themselves, are not meant to be a comprehensive source of information.
To take advantage of the global knowledge base known as the Internet, I have included numerous hyperlinks to external web sites (like the Wikipedia, USGS, NASA, etc.). Follow the links and scan them for relevant info. The information from linked web sites is meant to supplement and reinforce the lecture notes – you won’t be responsible for knowing everything contained in them.
As a distance learning student, you need to explore and understand the content more independently than in a traditional class. As always, I will help guide you through this learning adventure. Remember, email Dr. Bob if you have any questions about today’s lecture ([email protected]).Leave no questions behind!
Explore and have fun!Explore and have fun!
These notes and web links are your primary “lecture” content in this class. Additionally, various articles are assigned each week to supplement this “lecture” information. I believe you’ll have enough information to reference without having to purchase a costly textbook.
Amount of gas (water) in the magma
> As magma rises, P decreases & water turns to
steam that
can propel the eruption
> More gas (water) = more explosive
> Less gas (water) = less explosive
What Controls Eruptions?What Controls Eruptions?VolcanoesVolcanoes
Felsic lavas are more viscous
(higher wt% SiO2, lower T = high viscosity = more
“sticky”)
Magma composition
Mafic lavas are more fluid
(lower wt% SiO2, higher T = low viscosity = flow easily)
> Viscosity strongly influenced by wt% SiO2,
temperature, etc.
(more explosive
eruptions)
(less explosive eruptions)
What Controls Eruptions?What Controls Eruptions?VolcanoesVolcanoes
http://www.mc.maricopa.edu/dept/d43/glg/Study_Aids/VolcanoReview_2004.pdf
Volcanism Review TableVolcanism Review TableVolcanoesVolcanoes
Current volcanic eruptions
http://volcano.und.nodak.edu/vwdocs/current_volcs/current.html
Volcanoes of the WorldVolcanoes of the WorldVolcanoesVolcanoes
Flood BasaltsFlood BasaltsVolcano TypesVolcano Types
VolcanoesVolcanoes
Flood BasaltsFlood BasaltsVolcano TypesVolcano Types
VolcanoesVolcanoes
Deccan Traps (India)
Columbia River (USA)
Flood BasaltsFlood BasaltsVolcano TypesVolcano Types
VolcanoesVolcanoes
Shield VolcanoesShield VolcanoesVolcano TypesVolcano Types
VolcanoesVolcanoes
Mauna Loa (USA)
Fernandina (Galapagos Islands, Ecuador)
Shield VolcanoesShield VolcanoesVolcano TypesVolcano Types
VolcanoesVolcanoes
Joes Hill (AZ)
~11 Mya
Arlington Mesa (AZ)
1.3 Mya
Shield VolcanoesShield VolcanoesVolcano TypesVolcano Types
VolcanoesVolcanoes
Cinder/Scoria ConesCinder/Scoria ConesVolcano TypesVolcano Types
VolcanoesVolcanoes
Cerro Negro (Nicaragua)
Paricutin (Mexico)
Cinder/Scoria ConesCinder/Scoria ConesVolcano TypesVolcano Types
VolcanoesVolcanoes
Sunset Crater (AZ)SP Crater (AZ)
71,000 years ago 800 years ago
Cinder/Scoria ConesCinder/Scoria ConesVolcano TypesVolcano Types
VolcanoesVolcanoes
StratovolcanoesStratovolcanoesVolcano TypesVolcano Types
VolcanoesVolcanoes
Mt. Saint Helens (WA, USA) Mt. Fuji (Japan)
Mount Mayon (Philippines)Popocatapetl (Mexico)
StratovolcanoesStratovolcanoesVolcano TypesVolcano Types
VolcanoesVolcanoes
500 Kya
San Francisco Peaks (AZ, USA)
StratovolcanoesStratovolcanoesVolcano TypesVolcano Types
VolcanoesVolcanoes
Lava DomesLava DomesVolcano TypesVolcano Types
VolcanoesVolcanoes
Mount Unzen (Japan)
Mount Saint Helens (WA, USA)
Lava DomesLava DomesVolcano TypesVolcano Types
VolcanoesVolcanoes
Sugarloaf Mountain (AZ, USA)
Elden Mountain (AZ, USA)
Lava DomesLava DomesVolcano TypesVolcano Types
VolcanoesVolcanoes
Yellowstone (WY, USA) Long Valley (CA, USA)
Valles (NM, USA) Krakatau (Indonesia)
CalderasCalderasVolcano TypesVolcano Types
VolcanoesVolcanoes
Superstition Mountains (AZ, USA)
Chiricahua Mountains (AZ, USA)
CalderasCalderasVolcano TypesVolcano Types
VolcanoesVolcanoes
WWW Links in this LectureWWW Links in this Lecture
> Viscosity - http://en.wikipedia.org/wiki/Viscosity
> Mafic - http://en.wikipedia.org/wiki/Mafic
> Felsic - http://en.wikipedia.org/wiki/Felsic
> Volcanism review table - http://www.mc.maricopa.edu/dept/d43/glg/Study_Aids/VolcanoReview_2004.pdf
> Current volcanic eruptions -
http://volcano.und.nodak.edu/vwdocs/current_volcs/current.html
> Flood Basalt - http://en.wikipedia.org/wiki/Flood_basalt
> Shield volcano - http://en.wikipedia.org/wiki/Shield_volcano
> Cinder cone - http://en.wikipedia.org/wiki/Scoria_cone#Cinder_cone
> Stratovolcano - http://en.wikipedia.org/wiki/Stratovolcano
> Lava dome - http://en.wikipedia.org/wiki/Lava_dome
> Caldera - http://en.wikipedia.org/wiki/Caldera
VolcanoesVolcanoes