Chapter 3 Flashcards
What would happen if the internal heat engine stopped working and the external heat engine kept working?
The earth would be slowly leveled and it would read equilibrium.
What is the rock cycle?
An igneous rock erodes and turns into sediment then through the process of lithification it is glued together into sedimentary rock. That Sedimentary rock is eventually buried deep inside of the earth and because of heat and pressure it is turned into a Metamorphic rock through metamorphism. It is then melted again and turned into magma and when that magma cools Igneous rock is formed and it starts all over.
What is an intrusive igneous rock?
Rocks that were created under the surface of the earth.
How are plate tectonics related to the rock cycle?
At plate boundaries their is a lot of heat and pressure and magma is often formed melting the metamorphic rock creating magma.
How large are the grains in intrusive rocks?
Large because they had lots of time to grow.
How large are the grains in extrusive rocks?
Small because they were often given little to no time to form.
What is a contact?
A surface that separates different rock types.
Country Rock
Any rock that was older than and intruded by an igneous body.
Xenoliths
Fragments of rock distinct from the igneous rock in which it is enclosed.
How are igneous rocks named?
Based on their texture and chemical composition.
Texture
A rocks appearance with respect to the size, shape, and arrangement of its grains or other constituents.
Crystalline Rocks
Made up of interlocking crystals.
Glassy Rocks
Composed primarily of glass and contain few if any crystals.
Fragmental Rocks
composed of fragments of igneous material.
Aphanitic
Usually extrusive rocks with crystals that are to small to see easily with the naked eye.
Phaneritic
Texture in which the crystals making up an igneous rock are distinguishable without using a microscope.
Pegmatite
Extremely coarse grained igneous rock.
Phenocrysts
Any of the large crystals in porphyritic igneous rock.
Porphyritic Texture
An igneous rock in which large crystals are enclosed in a matrix of much finer-grained minerals or obsidian.
Vesicles
A cavity in volcanic rock caused by gas in lava.
Scoria
A highly vesicular basalt, actually contains more gas space than rock.
Pumice
A rock that is created by extremely frothy lava.
Pyroclasts
Fragment of rock formed by volcanic explosion.
Tuff
A rock formed from fine grained pyroclastic particles.
What are the 4 types of silica igneous rocks?
Felsic, Intermediate, Mafic, and Ultramafic.
what are the characteristics of diorite?
Course-grained igneous rock of intermediate composition. Up to half of the rock is plagioclase feldspar and the rest is ferromagnesian minerals.
What kind is a rock that mafic magma forms?
Gabbro
What is an example of an ultramafic rock?
Komatiite peridotite
Geothermal Gradient
The rate at which temperature increases with increasing depth.
What is solidus
The temperature at which rock melts.
What is decompression Melting?
When a rock moves closer to the crust and begins to melt because of a decrease in pressure.
Flux Melting
When a rocks melting temperature is reduced because of water.
What is Bowen’s reaction Series
Melting powdered rock, cooling the melt to a given temperature, and then observing the mineral present in the cooled rock.
discontinuous Branch
The left hand side of the diagram describes the formation of the ferromagnesian minerals olivine, pyroxene, amphibole, and biotite.
differentiation
Separation of different ingredients from an originally homogeneous mixture.
Intrusive structure
A body of intrusive rock classified on the basis of size, shape, and relationship to surrounding rocks.
Volcanic neck
An intrusive structure that apparently represents magma that solidified within the throat of a volcano
Discordant
The body is not parallel to any latering in the country rock.
What is a Sill?
A tabular intrusive structure concordant with the country rock. In similar words its parallel with the surrounding rocks.
Pluton
A body of magma or igneous rock that crystalizes at considerable depth.
diapirs
Blobs of magma.
What is the most common igneous rock?
Granite
