Examining natural disasters

long term forecasts of earthquakes

identify where and what areas are suceptible to earthquakesbased on historic datta and patterns

short term predictions of earthquakes

recognizing prcusors and predicting when and where risk is the highest in a narrow window of time. things like increase strain in rocks and changes in growing water levels.

p-wave

primarry compressional body wave that is the fastest to be felt or recorded. has a push and pull action.

L- wave

love wave ; a surafce wave that is sideways ground movements that causes the most damage to infrastructure. moves perpendicular.

distance formula for earthquakes

d= time delay/ (1/ vs - 1/vp)

Arrival time

time required for earthquake generated waves to reach the measuring station with seisometor

epicenter

point above actual focus that is source of earthquake

r-waves

rayleigh waves'; surface waves that move in a rolling motion direction like backwards ocean waves

focus or hypocenter

place of origin of earthquakes where energy radiates outwards off.

convergent plate boundry

when two tectonic plates move towards eachother and one may be denser the other causing other to decend below and this deeper are is where earthquakes come from

transform plate boundry

where two tectonic plates slide past one another

divergent plate boundry

when two tectonic plates pull apart from eachother.

seismogram

records seismic activity’records the early p waves, s waves and surface waves

seisomometer/seismograph

recordsof minute movements of ground todetect and measure earthquakes

energy formula for magnitude

E= 10^ 11.8+1.5R

differnece in energy formula

diff in E= 10^1.5(larger R- smaller R)

magnitude

a measurment of earthquake size based on amount of energy released

the richter scale

expresses amount of ground shaking and energy releases, found by amplitude valueon right scale and time on interval on left, each value is 1061 of the next.

intensity

amount of shaking and based on damage to infrastructure 

Modified Mercalli intensity scales

measures intensity based on how much damage.

s waves

secondary waves, shear body waves that move up and down or side to side perpendicular cannot pass through liquid or gas because it moves in two diff directions at same time. 60% speed of p waves

surface waves

r waves and l waves.55% speed of p wave

types of tectonic plates

oceanic plates and continental plates

geomagnetic reversal

earth’s magnetic field flips north and south poles switch places

convection currents

movements in the molten manic based on the rising of hot material and sinking of colder material that ultimatley drive the movement of tectonic plates

sea floor mapping 

measuring and charting physical features of ocean floor

continental drift

scientific theory that earth’s continents were once joined together then drifted over time

magnetite

naturally magnetic mineral

radiometric striping

dating ancient materials using the rate at which radioactive atoms undergo nuclear fission