Igneous Processes and Intrusive Bodies
Terms to learn:
magma Bowen's Reaction Series aphanitic
partial melting assimilation phaneritic
magma mixing porphyritic pyroclastic
pegmatitic vesicular intrusive (plutonic)
extrusive (volcanic) mafic felsic
Topic outline:
- Magma
- Igneous processes
- Magma evolution
- Differentiation
- Bowen’s reaction series - discontinuous branch – continuous branch
- Crystal settling
- Partial melting
- Assimilation
- Magma mixing
- Plate tectonic occurrence of igneous rocks
- Divergent boundaries – basalt
- Intraplate activity
- Convergent boundaries – andesite, granite
- Igneous rock – intrusive vs. extrusive
- Igneous rock identification
- texture
- mineral composition – mafic, felsic, intermediate, ultramafic
- volcanic/plutonic equivalents
When you are finished with this topic, you should be able to answer these questions:
- How can color and size of mineral grains in igneous rock give clues about the composition and cooling history of a magma?
- Distinguish between the two major kinds of igneous rock.
- In what ways can the composition of magma be changed?
- What does a porphyritic texture indicate about the formation of an igneous rock?
- Describe the differences between the continuous and discontinuous branches of Bowen's reaction series.
