{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

chapter4 - Chapter 4 Igneous Rocks Key Terms and Concepts...

Info icon This preview shows pages 1–10. Sign up to view the full content.

View Full Document Right Arrow Icon
    Chapter 4   Igneous Rocks
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
        Key Terms and Concepts Igneous rock, magma, lava, extrusive, intrusive Bowen’s reaction series Textures: aphanitic, phaneritic, porphyritic, glassy, pyroclastic, pegmatitic Compositions: peridotite (ultramafic) basalt/gabbro (mafic) andesite/diorite (intermediate) rhyolite/granite (felsic) Generating magma: What causes rocks to melt? (PT phase diagrams) Lower Pressure (and even lower T) Add water (dehydration reactions) Raise Temperature Evolution of magmas (fractional crystallization, assimilation, magma mixing) Partial melting (What happens to silica content?)
Image of page 2
        General characteristics  of magma Igneous rocks form as molten rock cools and solidifies Magma-usually silicate melt Produced by partial melting of any type of rock Magma at surface is called lava
Image of page 3

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
        General characteristics  of magma Extrusive - at the surface volcanic lavas, ash, cinders, and other pyroclastic debris fine grained, cooled rapidly usually dry Intrusive - inside the earth plutonic sill, dike, batholith, laccolith, etc. coarse grained, cooled slowly often rich in volatiles
Image of page 4
        General characteristics  of magma Consists of three components: Liquid = melt Solids = minerals crystallizing ( phenocrysts ) Gases = Volatiles (H 2 O, CO 2 SO 2 ) dissolved in the melt or forming bubbles or vesicles depends on pressure
Image of page 5

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
        General characteristics  of magma Crystallization of magma On cooling, various minerals crystallize at different temperatures Somewhat predictable order Different textures can result from same magma (intrusive vs. extrusive, water content, etc.)
Image of page 6
    Bowen’s reaction series Figure 4.23
Image of page 7

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
    Igneous textures Texture - the size, shape, and arrangement of minerals Factors affecting crystal size Rate of cooling Amount of H 2 O Role of nucleation sites and element mobility
Image of page 8
    Igneous textures
Image of page 9

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 10
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern