Earthquakes Flashcards
what it called when layers are of rocks are being crumpled and bent without breaking
folding
what is the fold called when it bends upwards?
anticline
what is the fold called when it bends downwards?
synclines
how did he Great Dividing Range form?
when two tectonic plates collided
how do rocks crack?
when huge forces are acting on them
what creates a fault?
when movement occurs along a crack
what is an example of a fault?
SA gulf region
what is the term used to describe a fault that is sideways?
strike- slip/ transcurrent fault
what is an example of a transcurrent fault?
San Andreas in California
what is the definition of fault and what does it allow?
a facture or a zone of facture between two blocks of rocks
this allows the blocks to move relative to each other
what happens if this movement occurs very rapdily?
earthquakes form
what happens if this movement occurs slowly?
the form of a creep
what do Earthquake movements form?
tremors or vibration in the earth surface
what happens when tremours or vibrations are very strong?
they form earthquakes
what is the epicenter?
the point directly above the point below the surface where the movement in the curst began
what is a focus?
the point where the earthquake began
where can tremors and minor earthquakes occur?
where the earths crust is really weak and also along faults
what are the types of way to measure the maginitidude of an earthquake?
seismograph, richter scale and Moment Maginitude (Mw) Scale
what is a microquake on the ritcher scale?
an earthquake that measure less than 2.0 and that are rarely felt by humans
what is a decetable earthquake on the richter scale?
an earthquake that measure 5.0 on the richter scale cause objects to rattle and shake
what is the richter scale a not good indication of?
the destructive power of an earthquake
what does moment magnitude scale measure?
the size of events based on how much energy they realase.
what are the 3 things that the Mw scale takes account for?
the rock type, the distance of movement along a fault and the area of the fault surface
what is a seismic wave?
they are waves of energy from the breaking of rock that travels through earth
how are seismic waves measured?
on a seismograph
what are the two main types of seismic waves?
body waves and surface waves
how do body waves travel?
through earths inner layers
how do surface waves travel?
along earths surface
what is an example of a surface wave?
ripples on water
what are the two types of body waves?
primary and secondary waves
what are the two types of surface waves?
love and raleigh waves
what is a primary wave?
first waves that travel the fastest through any type of medium
what is a secondary wave?
rarely causes sifnigifcant damage and also can only travel through a solid medium
what is another name for a primary wave?
compression wave
what is another name for a secondary wave?
shear wave
what is a raleigh wave?
slower than body waves and can travel through any types of surface. They carry the vast amount of energy felt
what is a love way?
they’re the most destructive wave and also travel perpendicularly
what is two examples of earthquakes that happened in australia and state there maginude?
Newcastle; 5.6
Tennat Creek; 6.7
what are the name used for people who study earthquake?
seismologists
what is the full form od DART?
Deep ocean assessment and reporting of tsunamis
what is a DART bouys?
an early warning system used to decect earthquakes and tsunamis
