Lecture 11 Flashcards
What are the three rock types?
Igneous
Sedimentary
Metamorphic
What is igneous rock?
Rocks formed by solidification of molten magma. These can be found on the earths surface or under the surface
What are the two types of igneous rock?
Intrusive igneous rock: Rock inside or under the earths surface
Extrinsic igneous rock: rock formed on the outside of the earths surface
What is denudation?
Wearing down of a landmass that can expose an intrusive igneous rock
What is weathering?
The breakdown of rock by physical, chemical and biological ways
What do subduction zones do?
Bring rock back to the mantle
What are the four measures of geologic time?
Eons, eras, period and epochs
What is the order from longest to shortest geologic time measurements
Eons > eras > period > epoch
What is uniformitarianism?
Landforms on the earths surface are caused by slow geomorphic processes not sudden events
What is catastrophism?
Sudden events shaping modern landforms
True or False:
Catastrophism and uniformitarianism are very similar theories
False they are opposite
What theory is evolution based on?
Uniformitarianism
What is sedimentary rock?
Formed by the burial, compression and chemical modification of deposited weathered debris
What is a metamorphic rock?
Heat or pressure physically or chemically changing a rock.
What are rocks made up of?
Elements
What are the four types of igneous rock? And an example of each. And name one rock that is the exception
Felsic: granite Mafic: basalt Intermediate: andesite Ultramafic: peridotite Exception: obsidian
Give a two examples of sedimentary rocks.
Conglomerate and sandstone
What are two examples of metamorphic rock?
Slate and shale
What are the three layers of the earth?
core, mantle, crust
What two elements make up the earths core?
Iron and nickel
What defines the two sections of the earths core?
Inner core is solid
Outer core is liquid
What is the origin of all rocks?
Magma.
What differs the asthenosphere from the rest of the mantle?
It is the upper portion of the mantle that is made of more ridges rocks
What type of rock is the upper mantle made up off?
Ultramafic igneous rock
How does the lower mantle move?
As a hot plastic
What is the lithosphere?
Includes crust and upper most portion of the mantle and it glides over the rest of the mantle. This is the location where earthquakes volcanoes and continental drift.
What are the two types of crust?
Oceanic which is thinner and continental which is thicker
Define isostacy.
The rising and sinking of tectonic plates due to weight distributed on a point. Glaciers have this affect on tectonic plates making them sink, then in a delayed reaction once the ice melts the plates rebound.
What are four pieces of evidence supporting continental drift?
Fossils, paleoclimatic regions, puzzle piece fit, rock and mountain ranges.
What pushed the continents apart?
Oceanic ridges.
What is older continental crust or oceanic crust?
Continental crust, because oceanic crust moves quickly into subduction zones refreshing every 200 million years
Define a dyke.
Thin vertical veins of igneous rock that cool, lots of minerals
What is a sill?
Planes of solidified magma
Define batholith.
Plutonic masses of intrusive rock
What is a volcanic pipe?
Dyke reaching the surface
Name four crustal formation processes.
Dyke
Sill
Batholith
Volcanic pipe
Define a mountain.
An area of land that rises abruptly from the surrounding region. Mountains form in belts from hotspots. Some can be of volcanic origin or can form underwater
Name four types of folds.
Monocline: slight bend in parallel lines
Anticline: upward fold
Syncline: downward fold
Recumbent: folded centres turned horizontal
Name the four types of faults.
Normal, reverse, graben, Horst
What are the four models of landform development.
Structural landforms, weathering landforms, erosional landforms, depositional landforms.
What are structural landforms?
Created by large quantity hardening of magma or large movements due to plate tectonics
Examples: shield, fold mountains, rift valleys, volcanoes
How are weathering landforms created?
By physical, chemical and biological weathering
Examples: karst, patterned ground, soil profiles
How are erosional landforms created?
Formed by the removal of sediment by wind water and glaciers or gravity
Examples: river valleys, glacial valleys, costal cliffs
How are depositional landforms created?
Formed by deposited sediments, these can be altered by heat, pressure or chemicals
What is a polygenic landform?
When a landforms falls into multiple categories
What initially formed earths atmosphere?
Volcanic activity
True or False:
The earths core is magnetic.
True
What has the most volume, the core, the mantle or the crust?
Mantle
What are the three geological processes?
Solidification: igneous
Metamorphic: metamorphic
Lithification: sedimentary
Name the six geological provinces.
Shield Platform Orogen Basin Large igneous province Extended continental crust
What are the three types of plate boundary?
Divergent
Convergent
Transform
What is a divergent plate boundary?
A constructive boundary where the plates move apart
What is a convergent plate boundary?
Destructive boundary where plates come together
What is a transform plate boundary?
Plates sliding past one another
