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The oceanic crust is made out of
basalt (extrusive igneous=small crystals)
The continental crust is made out of
granite (intrusive igneous=large crystals)
The mantle is made out of
iron, magnesium, and silicon to nickel
Consistency of the mantle
relatively solid to plasticy
The inner core is made out
Solid iron and nickel
The outer core is made of
liquid iron
Oceanic crust is ____ than continental crust
More dense
Thickness in miles/kms for the crust
5-25 miles, 8-40 kms
Thickness in miles/kms for the mantle
1800 miles, 2900kms
Thickness of the liquid outer core and the solid inner core
2200 miles, 3500kms
Thickness of the crust to the solid inner core
6400kms and 4000 miles
What are minerals
Naturally occurring inorganic substances and are the building blocks for rocks
What are rocks
the aggregate of mineral particles and are based on formation
What are the 3 types of rocks
igneous, sedimentary, metamorphic
The rock cycle’s first few steps
Weathering, transportation, deposition, then turns into SEDIMENTS, lithification (Compaction and cementation), then turns into SEDIMENTARY ROCKS. All rocks that are formed go through uplift and exposure which leads to weathering.
The rock cycle’s steps after sedimentary rocks are formed
Metamorphism occurs, then turns into METAMORPHIC ROCKS, melting into magma, then crystalization leads to INTRUSIVE IGNEOUS ROCKS and consolidation leads to EXTRUSIVE IGNEOUS ROCKS.
What type of rock is volcanic
Extrusive igneous
What type of rock is plutonic
intrusive igneous
How are sedimentary rocks formed
compaction of sediments
How is metamorphic rock formed
Heat and pressure pushing towards heat
How is igneous rock formed
Formed when molten magma cools, solidifies, and crystalizes
How are intrusive rocks formed
cooling and solidifying beneath the surface (occurs more slowly because of surrounding pressure and insulation)
How are extrusive rocks formed
Cooling and solidifying upon breaking through the surface (occurs much faster because of contact with air or water)
What does rapid cooling look like
small pieces of rocks become tightly compacted
What does slow cooling look like
Bigger pieces further apart become compacted, but they are bigger pieces
Is cooling slower/faster and is crystalization larger or smaller in intrusive rocks
Slower, larger
Is cooling slower/faster and is crystalization larger or smaller in extrusive rocks
Faster, smaller
Intrusive rock examples
Course-grained granite
Extrusive rock examples
Fine-grained basalt and glassy obsidian
How is sedimentary rocks formed (more in depth answer)
External processes (weathering and erosion) help disintegrate rocks into sediments. Sediments are then transported via water, wind, ice, and or/gravity and deposited in basins where layers form (strata)
Sedimentary rock examples
Sandstone, limestone
How is metamorphic rock formed (more in-depth answer)
Rocks that have been drastically changed from heat and /or pressure. Usually, very different from pre-metamorphic state (harder, more compact)
Changes/ties that are identifiable
Shale to slate, granite to gneiss, limestone to marble
Who created the original idea of the origins of continents / Pangea
Alfred Wegener
Who was Vladimir Korp
He made the Koeppen system (climates)
How long ago was pangea
225 million years ago
How long ago was laurasia
135 million years ago
When did the dinosaurs go extinct?
65 million years ago
What did Pangea break into?
Gondwana and laurasia
How much do plate tectonics move per year
an inch
How many major plates are there?
7
How many intermediate plates are there?
7-8
How are they moved?
convection currents of magma from the upper mantle move them within the asthenosphere
What is the ring of fire?
Very intense area with frequent earthquakes and volcanoes
What is the lithosphere also known as?
The crust and upper mantle and the rockosphere
What is plate divergence?
Plates moving away from one another or rifting within a major plate
Examples of plate divergence
Mid-oceanic ridge / mid Atlantic ridge, east African rift, Lake Baikal
What is the process that happens at the mid-oceanic ridges
seafloor spreading
What area on earth is the most deepest and volumnous
Lake Baikal
What are grabens
depressions in land caused by faults
Example of a graben
The Niagara falls
What is seafloor spreading?
magma rises and pushes through the upper mantle, forcing the oceanic crust outward near continents on each side.
What are ocean ridges
Shallow parts of the ocean floor: rift and ridge and are sites of seafloor spreading (mid-ocean ridges)
What are trenches
Narrow belts of deep water (>6km) sites of subduction
Deepest trench
The mariana trench
Where do continental rift valleys develop
Where divergence takes place within a continent. As spreading proceeds, blocks of crust drop down, forming a rift valley.
Continental rift valley example
Lake Tanganyika
What is plate convergence?
Plates that collide
What plate subducts in a convergent boundary?
The denser plate (crust) subducts the lighter one
3 types of convergence
oceanic/continental, oceanic/oceanic, continental/continental
Oceanic-continental
The denser oceanic crust subducts continental crust upon contact, followed by oceanic crust sinking into the mantle.
What forms on land and in the subduction zone in oceanic/continental
Mountain ranges on land, oceanic trench forms in subduction zone
Example of oceanic/continental
Andes Mountains O
Oceanic-Oceanic
Older, denser plate will subduct younger one. Volcanoes often develop (island arcs)
Examples of oceanic-oceanic boundary
Aleutians of Alaska, Islands of Japan, Islands of Caribbean, lesser Antilles
What is found in the subduction zones of ocean-oceanic?
Large earthquakes
Continental-continental
Continental crust is too buoyant for much subduction, thus huge mountain ranges develop, volcanism is rare
Examples of continental/continental
Mt. Everest in the Himalayas
How did the Himalayas form?
India’s subcontinent collided with the Eurasian landmass/plate
Transform boundary
Two plates moving past one another laterally. Along great fractures called transform faults
Transform boundary example
San Andreas Fault
Mantle plumes
rise of magma to the surface in the interior regions of a plate. Often, the hotspot stays in place, but landforms move with the drifting plate.
What are mantle plumes
hot spots
Example of a hot spot
Yellowstone park
Terrane
Mass of lithosphere carried a long distance by a drifting plate. It eventually converges with another plate. (too buoyant for subduction, so it is rather fused (accreted) to the other plate. It is a key reason for continental expansion.
Where are volcanoes generally found
Mostly on plate boundaries
what percent of volcanoes is found in the ring of fire?
75%
How many actives volcanoes are there? where are they mostly located?
500, mostly underwater
What is pyroclastic material?
Fragmented material ‘shot out’ during eruptions. (rock fragments, lava, blobs, ash, dust)
The chemical structure of magma determines what?
The nature of the lava/pyroclastic material and the explosive capabilities of the volcanoes
Lava and ash flows can produce what?
Fertile soils
Many lava flows are not extruded from volcanoes, but what?
Fissures. Many fissures create floor basalts (accumulated lava layers)
Shield volcanoes
Not steep-sided. Hawaiian islands are composed of numerous shield volcanoes
What does basaltic lava (fluid and easy flowing) form? (Shield volcanoes)
usually forms low lying shield volcanoes
Composite/strato volcanoes tend to
erupt more violently.
Composite/strato volcano eruptions
alternate between lava-based lava-based, non violent eruptions and ash based, violent eruptions. Because of this, layers/strata are formed.
Composite/strato volcanoes are
generally very tall and steep sided
Lava/plug domes have
very viscous lava that doesn’t flow far.
Lava usually
bulges up from the vent and the dome will grow by expansion from below and within.
Lava/plug domes are generally
not very tall and irregularly shaped.
Shield volcano examples
Hawaiian islands, Tahiti
Composite (strato volcanoes) examples
Mt Fuji Japan, Mt. Rainier Washington, Mt. Shasta CA, Mt. Vesuvius Italy, Mt. St, Helens Washington.
Lava dome/ plug dome examples
Lassen Peak, CA, Mono Craters CA
Cinder cone examples
Paricutin Mexico, Sunset crater, Arizona
Cinder cones are
small and generally created by loose pyroclastic material
Caldera
On occasion, a volcano may expel so much material that the summit collapes into its emptied magma chamber. A crater then forms, usually surrounded by steep cliffs on all sides.
Caldera example
Crater lake, Oregon
Earthquakes
A shaking or trembling of the earth that is volcanic or tectonic in origin
3 Main techtonic causes
Considerable compression causes crust/rocks to fold. Considerable tension causes the crust/rocks to collapse. Plates moving laterally past one another can cause friction. Vibration signifies the release of energy caused by sudden movement.
Earthquake scale
Richter scale
Note 
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