Transcript CH 4 Review Intrusives

CH 4 - Intrusives
Are you ready for the test?
What is country rock?
• Existing rock already formed.
What are intrusives?
• Igneous rock formed underground
between country rock.
What does concordant mean?
• Parallel to country rock
What does discordant mean?
• Perpendicular to country rock.
4 ways to classify intrusives
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Size
Shape
Depth
Relation to country rock
Most abundant intrusive rock?
• Granite
Why is erosion important to
studying intrusives?
• Expose intrusives.
Shallow vs deep intrusives make
what type of rocks?
• Shallow – small grained crystals;
aphanitic, like basalt
• Deep – large grained crystals; phaneritic,
like granite
What are xenoliths?
• Alien rocks
Know real pictures of intrusives.
Name the intrusives:
Name the intrusives:
Know this picture
Use Bowen’s Reaction Series:
Rock Textures
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Physical Conditions
What minerals in what rocks?
What minerals form in what order?
What rocks & minerals come from what magma?
What rocks & minerals are most/least stable?
What minerals form at what temps?
Discontinuous vs continuous branches
Aphanitic vs Phranetic rocks
What rocks come from Mafic
magma?
• Basalt, Gabbro
What rocks come from Felsic
magma?
• Granite, Rhyolite
What rocks come from
Intermediate magma?
• Andesite, diorite
What rocks are found at divergent
boundaries?
• Mafic - Basalt, Gabbro
What rocks are found at
convergent boundaries?
• Intermediate – andesite, diorite
• Felsic – granite, rhyolite
What three factors can lower
minerals’ melting points?
• Pressure
• Mixing minerals
• Pressurized Water
What are 4 ways magma can
change?
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Differentiation; crystal settling
Magma mixing
Assimilation
Partial Melting
Be able to identify 9 igneous rocks.
Obsidian
Pumice
Gabbro
Andesite
Granite
Rhyolite
Fine-grained Basalt
Vesicular basalt
Porphorytic Basalt