Continental Drift Flashcards
Alfred Wegner is known for what
proposing the idea of continental drift
what is the evidence of continental drift
continents fit like puzzle pieces
fossil distribution
climate belts
radiating glacial patterns
rock unit and landforms
Henry Hess did what
proposed seafloor spreading
what is the evidence of seafloor spreading
bathymetric mapping
paleomagnetism
types of plate boundaries
divergent
convergent
transform
what is the divergent boundary
when plates pull away
-mid ocean ridge
what is the convergent boundary
when plates move towards each other
ocean & continental convergence
a trench & a continental volcanic arm is created
ocean & ocean convergence
a trench and an island volcanic arm is created
continental & continental convergence
mountains are created
what is a transform boundary
plates rub against one another
what is a ridge
where plates pull apart
active vs passive margins
active margins are actively moving
passive margins are inside of a plate, where plates are NOT colliding
trench & collision zone
where plates come together
faults
a crack that occurs when tectonics put pressure/stress on a rock
types of faults
compression: convergent
tension: divergent
shear: transform
elastic rebound
when energy is stored in a rock, it distorts the appearance
ductile vs brittle elastic rebound
ductile: pressure is applied so it bends in the middle
brittle: pressure is applied and it breaks
characteristics of an earthquake
shear fault
brittle elastic rebound
epicenter
the land surface directly above the focus
focus
the location where fault slip occurs
faults
breaks in the crust
earthquake waves
P waves, S waves, Surface waves
P waves
body waves: moves through interior
fastest seismic wave
travels by compressing and expanding
S waves
body waves: moves through interior
slower wave
moves through solids only
moving back & forth
surface waves
slowest & most destructive
(L)ove waves: broken along the lines
(R)ayleight: rolling motion
intensity vs magnitude
Intensity is based on the damage observed
magnitude is the power behind the fault