2/11 science test😕 Flashcards
P waves
- primary
- faster
- goes through solid, liquids, gasses
- goes thru core
- compression wide
- longitudinal
- can bend between layer
- shadow zone: 105 - 140
s waves
- secondary
- slower
- solids only
- stops at core
- shear wave
- transversal
- shadow zone- at 105
Lithosphere
- brittle (breaks = quakes)
- includes all crust
- upper mantle
Radio active elements
U- uranium
Th- thorium
K - potassium
proclastic flow
Dense of very hot ash, solid lava pieces and hot gas that flow rapidly downslope at speed of 100 - 700 km/yr. Destroyed by both air and land.
lava
slow creeping and burns everything in path
Ring of fire
- 90% of world earthquakes
- 75% of worlds volcanoes
- 40,000 km long
- 22 of 25 largest eruptions occurred here
- pacific plate is the largest tectonic plate
- most of the active volcanoes are UNDERWATER
Krakatoa
- 1883 eruption made the loudest sound in history
- heard 1000’s miles away
- many killed by proyclastic and tsunami (36000)
- hot ash shut up 80 km in the air
- temps dropped all over the world and lasted years
- darkened the sky for 5 days, red sunsets
- it collapsed into the caldera below sea level
- Anak Krakaita emerged in 1927
- shocked wave from the final explosion traveled the world 7 times in 5 days
convection cells
rising and sinking of hot magma as it heats(less dense) and cools (denser) in the mantle. This also heats the earth
divergent
- forms mid-ocean ridge
- seafloor spreading
- mid-Atlantic ridge runs through Iceland
- Basalt is the ingenious rock on seafloor
- underwater mountain chains
Transform
most common reason for earthquakes b/c plates get stuck.
convergent
- 2 plates collide
- creates volcanoes, mountains, trenches
- 3 types - ocean- continent , ocean - ocean, continent - continent
mechanical layer
- ) lithosphere
- ) Asthenosphere
- ) mesosphere
- ) outer core
- ) inner core
compositional layers
- the crust (oceanic and continental)
- mantle
- core
continental crust
- thicker
- less dense
- where we live
oceanic crust
- thinner but denser
- will subduct under continental crust
- younger ocean crust
Asthenosphere
sludgy like oobleck and toothpaste
outer core
liquid
inner core
- solid
- mostly iron, some nickle
wagner
discovered. ..
- continental drift - all continents once together(Pangea) then the plates drifted apart to present day location
- evidence - fossils of plants/animals on different continents, continents fit like a puzzle
plate boundaries
- convergent (subduction)
- divergent
- transform
tectonic plates
movement is the most powerful force on earth
marina trench
- crescent shaped
- 7 miles at the deepest point
- challenger deep, temp just above freezing
- James Cameron went down in a submersible for 3 hours to explore
- pacific ocean
- Mt Everest could fit inside and still miss ocean top by 2.1km
- 5 people gone down
harry Hess
discovered seafloor spreading
Appalachian mt
- rounded
- colorful tress
- 4 seasons
- tallest peak (6400 ft)
- Maine to north GA (eastern US)
- 200 miles long
- wildfires
Rocky Mt
- Canada to New Mexico
- tallest peak over 14000ft
- snow-capped
- jagged
- steep
- lots of rivers/ lakes
- western US
- 3000 miles
- has wildfires
Himalayas
- Asia
- where Indian and Eurasian plate crash
- jagged and steep ( many over 2000 ft)
- Mt Everest is 8850km (29,000 ft)
- avalanches
- 300 have died climbing mt everst
- 2900 km long
volcanoes
- mostly found at “ring of fire”
- 75% of “ring of fire”
- pyroclastic flow
- hot rock, poisonous, gases, burning ash bellows down the volcanoes.
- kills more people
- none on Australia
- water will decrease the melting point in the mantle
- emits water vapor and co2
- some form over hotspots like Hawaii and Yellowstone
Earthquakes
- plates releasing the stress and energy in rocks
- seismic waves
- 80% are found in the ring of fire and at fault
- New Madrid fault near Nashville and formed Reelfoot lake
- San Andres fault is in CA
- can trigger tsunamis
- set off fires
- japan 2011😭
subdtuction happens …
- when denser plates sink below the fewer plates slide back into the mantle
- earth recycled itself
- occurs around the ring of fire.
studying how waves move
help scientise learn more about the interior of the earth.
