302-Lecture 3

General Outline

Igneous Activity and Landforms

 

I.   Extrusive Igneous Landforms and Volcanic Activity

A.   Composite (strato) volcanoes

1.     stratigraphy and structure

2.     composition of magma, SiO₂ and water content

3.     pyroclastic eruptions, nuee ardente (Martinique)

4.     erosional remnants: volcanic necks and dikes

5.     examples (Cascades, Aleutians, Fiji, Andes), plate margins

B.    Shield Volcanoes

1.     size, structure

2.     deposits, lava types

3.     interplate location, hot spots

4.     comparison between composite and shield volcanoes:

a.     VEI

b.     resulting landforms

c.     extraterrestrial examples

C.    Calderas

1.     formation and deposits

2.     geysers

D.   Flood Basalts

1.     formation, association with hot spots and mantle plumes

2.     examples

3.     columnar basalt

       E.       Earth’s igneous provinces

II.   Intrusive (Plutonic) Igneous Processes and Rock Structures

A.   Terminology and formation

a.     exhumation

b.     examples

      c.   batholiths of North America