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IGNEOUS LANDFORMS

A. INTRODUCTION

• Driving framework; constructive processes

• Rift zones

• Subduction zones

• Hot spots

B. VOLCANO TYPES

Shield Volcanoes

largest in size gently sloping effusive eruptions; basalt oceanic hot spots, oceanic rift zones Image credit: USGS Hawaiian Volcanoes Observatory, Kilauea, May 2004. http://hvo.wr.usgs.gov/kilauea/update/archive/2004/May/1-10.html

Image credit: D. Little, USGS. Photo Glossary of Volcano Terms. http://volcanoes.usgs.gov/Products/Pglossary/ShieldVolcano.html Image credit: C. Heliker, USGS Hawaiian Volcanoes Observatory, Pu`u `O`o lava fountain. http://hvo.wr.usgs.gov/gallery/kilauea/erupt/19930221_caption.html

Composite (strato) Volcanoes

• intermediate in size (but still big)

• steep-sided

• explosive eruptions; andesite & rhyolite

• subduction zones, continental hotspots, continental rift zones

photo credit: Donald A. Swanson, USGS/Cascades Volcano Observatory

photo credit: Lyn Topinka, USGS/Cascades Volcano Observatory

 

Cinder Cones smallest in size steepest sides mixed activity; primarily basalt rift zones, subduction zones, hot spots

Image credit: Priest, et al. USGS Factsheet 017-01. The San Francisco Volcanic Field, Arizona. http://pubs.usgs.gov/fs/2001/fs017-01/

C. OTHER VOLCANIC LANDFORMS

• Craters and Calderas    
  

  
  Image credit: Mike Doukas, USGS/Cascades Volcano Observatory http://vulcan.wr.usgs.gov/Volcanoes/CraterLake/images.html

• Lava Flows  

  Image credit: R.W. Decker, USGS/Hawaiian Volcano Observatory http://hvo.wr.usgs.gov/gallery/maunaloa/1984/1984erupt.html

  photo credit: J.D. Griggs, USGS/Hawaiian Volcano Observatory http://hvo.wr.usgs.gov/gallery/maunaloa/1984/1984erupt.html

• Debris Flows and Lahars

  Mount Saint Helens debris avalanche Image credit: Lyn Topinka, USGS Cascades Volcano Observatory http://vulcan.wr.usgs.gov/Volcanoes/MSH/Images/debris_aval_images.html

  Mount Saint Helens lahar (mud flow) photo credit: Lyn Topinka, USGS/Cascades Volcano Observatory http://vulcan.wr.usgs.gov/Volcanoes/MSH/Images/mudflow_images.html

• Pyroclastic Flows

  Image credit: C. Newhall, USGS Volcano Hazards Program. Photo Glossary of Volcano Terms. http://volcanoes.usgs.gov/Products/Pglossary/PyroFlow.html

  Image credit: USGS Volcano Hazards Program. Pyroclastic Flow at Mt. St. Helens. http://volcanoes.usgs.gov/Hazards/What/PF/PFMSH.html

D. INTRUSIVE IGNEOUS LANDFORMS

• Batholiths

• Sills & dikes

  Image credits: N.C. Heywood (used with permission)

• Volcanic Necks

  
  Image credit: N.C. Heywood (used with permission)

E. SUMMARY

• Driving force that builds up landscape

• Volcano types

• Volcanic landforms

• Intrusive igneous landforms