Download Earth Structure/Composition

PHYSICAL GEOGRAPHY FINAL EXAM STUDY GUIDE
EARTH MATERIALS: BE ABLE TO IDENTIFY MINERALS AND ROCKS LISTED BELOW!
ELEMENTS in the crust: Oxygen, Silicon, Aluminum, Iron, Calcium, Potassium, Sodium and Magnesium
MINERALS: Why is the difference between “Silicate” and “Nonsilicate” minerals? What do the terms “felsic”, “mafic” and
“ultramafic” mean in terms of elements that form a mineral?
Non-Silicates: Native Elements (Gold, Silver, Copper, Platinum) and Evaporites (Fluorite, Chlorite, Halite, Gypsum),: and
Silicates: Felsic: Quartz, Feldspars Mafic: Biotite Mica, Hornblende Ultramafic: Olivine
IGNEOUS: What does Texture and Mineral Composition have to do with identifying igneous rocks? Why do we use the Silica
molecule as an identifier of mineral composition? What do the terms “Felsic”, “Intermediate” and “Mafic” mean? What’s the
difference between Plutonic/Intrusive and Volcanic/Extrusive? How do you know the difference between these two? What
does the texture of an igneous rock tell you about the environment in which the igneous rock cooled? What do the terms
“Phaneritic” and “Aphanitic” texture mean?
(Plutonic) Intrusive, Phaneritic texture: Granite (Felsic); Diorite (Intermediate); Gabbro (Mafic)
(Volcanic) Extrusive, Aphanitic texture,: Rhyolite (Felsic); Andesite (Intermediate); Basalt (Mafic)
Plutons – Batholiths, Dikes, Sills
Pyroclasts: Nueé Ardente, Tuff, and Tephra
Volcanic Glass: Pumice, Obsidian
SEDIMENTARY: What type of environments? How are sedimentary rocks formed? What is lithification? How does
lithification work to change sediment particles to rock? What is the commercial value of sedimentary rocks?
Three types of sedimentary rocks:
Clastic: SHALES: Mudstone; Siltstone; Claystone: Sandstones: Conglomerates and Breccias
Chemically Precipitated: Inorganic: Limestone; Chert (Jasper, Agate) Organic: Coral, Chalk, Coquina
Organic: Coal (PeatLigniteBituminousAnthracite)
METAMORPHIC: WHAT
IS A METAMORPHIC ROCK?
WHAT
HAPPENS WHEN ROCKS UNDERGO METAMORPHISM?
WHAT
ARE THE FORCES
NEEDED TO EFFECT METAMORPHISM?
Types of metamorphic rocks: What’s the difference between foliated and non-foliated metamorphic rocks?
Foliated: Slate, Schist, Gneiss (Parent rock to metamorphic rock – limestone TO marble, quartz TO quartzite,)
Non-foliated: Marble, Quartzite
What are possible formation processes? What are the environments where metamorphism takes place? What is Contact
metamorphim? What is Regional metamorphism?
What do the Metamorphic grades: Low, Intermediate, and High mean in terms of temperature and pressure involved?
GEOLOGIC TIME
Eras: Precambrian, Paleozoic, Mesozoic, Cenozoic
What eras are known as the Age of Reptiles and the Age of Mammals?
Period: Paleozoic: Cambrian, Ordovician, Silurian, Devonian, Mississippian, Pennsylvanian, Permian
Mesozoic: Triassic, Jurassic, Cretaceous
Cenozoic: Tertiary, Quaternary
Epoch: (Cenozoic): Paleocene, Eocene, Oligocene, Miocene, Pliocene, Pleistocene, Holocene
Know the approximate beginning/endings for eras, periods, and epochs
What is the Permian Extinction? What is the K-T (Cretaceous-Tertiary) boundary extinction?
AGE-DATING TECHNIQUES: What are the principles used in Relative Dating? (Law of Original Horizontality; Law of
Superposition; Faunal Succession;, Lateral Continuity;, Cross-cutting relationships) How do each of these principles help us
date sedimentary layers? What is the science behind Absolute Dating that uses Radiometric techniques? What does the term
“half-life” mean in regards to radioactive elements/isotopes?
EARTH STRUCTURE/COMPOSITION
CORE - MANTLE – CRUST: WHAT ARE THE MAIN MINERALS THAT MAKE UP EACH LAYER?
What and where is the Lithosphere? What and where is the Asthenosphere?
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AT WHAT DEPTH IS EACH LAYER?
What is the difference between Continental Crust and Oceanic Crust? Which is more dense – continental or oceanic crust?
Which is thicker, yet more buoyant – continental or oceanic crust? Does the depth of the lithosphere and asthenosphere
differ in depth under the continents rather than under the oceans?
What was Alfred Wegener’s evidence that supported his Theory of Continental Drift? What is the Theory of Plate Tectonics?
What is the Evidence for this theory?
What are the proposed mechanisms for the movement of the plates?
What are Hot Spots/Mantle Plumes? What is their possible formation and what kind of landforms can be created?
WHAT ARE Lithospheric Plate Boundaries? Which boundaries are associated with Volcanism? Which boundaries are associated
with Earthquakes?
Can you name the two main types of Convergent boundaries? Can you give, identify and describe examples and description of
landforms possible with convergent boundaries? What are typical Subduction Zone features? What are typical Collision Zone
features?
What is a Divergent boundary? Can you give a description and examples of typical divergent boundary features?
What is a Transform boundary? Ca you give a description and examples of typical transform boundary features?
EARTH PROCESSES/LANDFORMS
Volcanoes: What is a volcano?
What are the three basic forms of volcanoes? Which of the three basic types is the most explosive? The least explosive?
Why is there a difference?
Can you describe, identify and give examples for each of these typical volcano types?
Shield - Stratovolcano (composite) - Cinder Cone – Plug Dome – Calderas
What are the explosivity controls on volcanic eruptions? What and how does magma rise? How and why does a volcano erupt?
What are the Rock melting processes?
What is the difference between a Felsic Magma eruption and a Mafic Magma eruption? How does temperature, viscosity and
chemical composition of a magma control explosivity?
What are Calderas? How are they formed? What is Krakatau and where is it located? What was Mt. Mazama (Crater Lake,
Oregon)? How did Crater Lake form? What is the Long Valley Caldera and where is it located? Why has this caldera been of
recent importance to geologists? What is Mt. St. Helens? What and where is the Cascade Range? How did this range form –
what tectonic setting created this range? What kinds of volcanoes are found in this range?
Diastrophism – Mountain Building
What is the difference between Isotasy and warping? Can you describe the three forces that shape the earth: compression,
extension, and shearing?
Can you describe and identify the various types of Folded structures including: Anticlines; Synclines; Recumbent folds;
Overturned folds? How are each formed?
What is a “Fault”? What is the “fault zone”? What is the “Fault Plane”?
Can you describe, identify and explain the various Fault structures and features including fault scarps, offsets, misplaced
streams? What is “dip” and what is “strike”? What do they tell us about a fault line?
Can you distinguish between the different Dip Slip Faults: Normal Fault; Reverse Fault; and Reverse Thrust? What does
“dip/slip” mean?
What is aTransform or Strike-Slip Fault? Give an example!
What are Horst and Graben? How are they formed? Name an example
What are Fault Block Mountains? How are they formed? Name an example
What are Folded Mountains? How are they formed? Name an example
What is an Earthquake? What are Body waves? Can you describe P-waves, S-waves? What and where is the Epicenter of an
earthquake? What and where is the Focus/Hypocenter of an earthquake?
What are the two systems used to measure earthquakes? What is the difference between the Richter Scale and the Mercalli
Scale?
What are the most Significant earthquakes in recent North American history
Can you describe and identify the consequences of earthquake: Tsunami, displacement, seiches, groundwater movement,
WEATHERING AND EROSION
Physical Weathering (Mechanical) – What is physical weathering? Where and how does it take place?
For each of the following weathering processes – can you describe and identify each one? Can you identify the most
susceptible rock types and locations for each of these processes?
Frost/Ice Action: Ice Shattering – Ice Heaving - Stone Rings - Pingoes
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Salt Crystal Growth: salt-wedging - cave-dwellers
Unloading: Exfoliation – spalling – susceptible rocks
Bioturbation: Animal burrowing - tree roots
Chemical Weathering – What is chemical weathering? Where and how does it take place?
For each of the following weathering processes – can you describe and identify each one? Can you identify the most
susceptible rock types and locations for each of these processes?
Hydrolysis: adding water molecularly
Oxidation: adding oxygen molecularly
Carbonic Acid dissolution: limestone susceptibility
Factors: Climate - Organisms in soil - Time - Mineral composition
MASS WASTING - MASS MOVEMENT How do each of these Causes/Factors play a role in accelerating or preventing
mass wasting? Gravity - friction - angle of slope - slope composition - vegetation - water in/on slope
What are the Triggers: Natural: - rains - earthquakes - volcanoes - gravity
Human: Mismanagement of soil/water - oversteepening/overburdening slopes – mining consequences
What are the Slow forms of mass wasting? How does Soil Creep differ from solifluction? Where is solifluction most likely to
occur?
What are the Fast forms of mass wasting? What is a Rockfall? What is a landslide? How does earthflow differ from a
slump?
How do Mudflows. Lahars, and Debris flows differ? What is the typical location for lahars? What is a typical
location for debris flows? How do Catchment Basins and Debris basins work to control debris flows?
GROUNDWATER – WHAT IS GROUNDWATER? WHERE IS IT FOUND?
Can you describe the various divisions within groundwater? What is the Phreatic Zone (Saturation Zone)?
What is the
Vadose Zone (Aeration Zone)
? In which zone (Phreatic or Vadose) is true groundwater found?
What is the Water Table; where is it located?
What are the physical characteristics of a good Aquifer? What is the difference between porosity and permeability?
What is the difference between a confined aquifer and an unconfined aquifer?
How are artesian wells formed? What is an aquiclude? How does an aquitard differ from an aquiclude?
How does a perched water table form?
What is a good rock material for aquifers? What kind of rock material makes an aquitard or aquiclude?
Can you describe and explain the following Groundwater Management Problems?
Land Subsidence?
Sources of Contamination? Salt Water Intrusion?
Legal issues?
Water Table lowering? Cone of Depression and Drawdown Effect?
Overdrawing/overpumping?
What is Karst Topography? How is karst topography formed? What are the typical bedrock types in a karst topography
area? Are there locations in United States? If so, where?
SURFACE WATER
The following are typical features involved with Slope Erosion: Rills; Gullies; and Arroyos. Can you identify each type?
What is a Stream Channel? How is it formed?
What is Stream Discharge? How is it measured? What are the factors that affect discharge?
What are the Stream Transportation mechanisms? How does a stream move its ‘load’ downstream?
What is Dissolved Load?
What is Suspended Load?
What is Bed Load: Saltation and Traction?
What is the difference between Stream Capacity and Stream Competence?
What is a Graded Stream? What is the Base Level for streams? What are the typical features present during each of the
“Ages” of a Stream - Youth - Maturity - Old Age – Rejuvenation? What is a Drainage Basin?
Divide? What is a Watershed? Can you describe each of the following Drainage Patterns:
What is a Drainage
Dendritic; Parallel;
Radial; Trellis; and Deranged? What are the typical surface landforms associated with each drainage patterns?
How and when are Floodplain features developed? What are backswamps, meander scars, oxbow lakes, stream terraces, and
Yazoo tributaries? How are Deltas formed?
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