geology 4 Flashcards
what is the inner core made of
solid nickel and iron
what is the outer core made of
liquid, iron
what is the mantle made of
iron-rich rock
semi-solid
top of mantle called the asthenosphere
what is the evidence that there was once a super continent
fit of continents
mountain chains and rock types
volcanoes and earthquake locations
glacial evidence
what are the two plate types
oceanic plates-made of basalt, dense
continental plates-made of granite, less dense
how do plates move
convection currents in the mantle
move very slowly
are constantly in motion
what are the 4 types of plate motions
converge-compression of plates
diverge-tension(pull apart)
transform-slide past eachother
subduction-ocean plate is pushed under crust
what is a hot spot
volcanoes that occur in the middle of a plate
no plate boundaries
plate moves-hot spots don’t
what is an earthquake
ground motion caused by a geological event
energy is transferred through the earths crust
what are the three types of earthquake waves and their characteristics
p-waves- primary waves,compression waves, move very fast
s-waves-secondary, shear waves, move slower than p-waves, do not travel through liquids
l-waves-slowest waves, most damaging, rolling motion, side to side motion
what is the epicenter and focus
epicenter-place on earths surface directly above the focus
focus-where the actual break occurs
what are the energy and ground displacement
energy released increases 32x(5 magnitude is 32x more energy than a 4)
ground displacement increases 10x (5 moves the ground 10x more than a 4)
what are the three ways to measure earthquake magnitude
richter scale-older system, not accurate for earthquakes far away from seismograph station
moment magnitude scale-more accurate at long distances
mercalli scale-measured by observation
what are primary effects of earthquakes
ground shaking
ground rupture
liquefaction
what are secondary effects of earthquakes
structure collapse
fires
flooding
starvation and disease
