earthquake general Flashcards
what causes earthquakes
when tectonic plates slip causing a release in energy and ground to shake
causes for plates slipping
friction volcanic eruption fracking nuclear bombs magma movement
what is a shallow eq
0 -50km
what is a mid depth earthquake
50- 300km
what is a deep eq
300km plus
types of waves
p
s
love
rayleigh
s wave type
transvers
p wave type
longitudinal
what are p waves fastes thru
solids and liquids
what are s waves slower thru
solids but very damaging
do s or p waves reach surface first
p waves
what can s waves travel through
just the mantle and not the core
what do p waves travel through
mantle and the core
what sort of motion are rayleigh waves
rolling
characteristic of love waves
slowest but most damaging
what effects impact of eq
location foundation material depth of focus land use preparation economic status
what are the two ways to measure eq
mercalli scale
richter scale
features of mercalli intensity scale
place specific 12 point scale
takes into account effects experienced
features of richter scale
easy to compare eq and scale is logarithmic
japanese eq management
prediction
preparation
prevention
response
how do they predict
past records
seismic monitoring
tsunami monitoring system
preparation
monthly eq drills education to raise awaness of risks annual eq simulations eq emergency kits risk maps and evacuation routes
how did the prevent
building regs now to reinforce buildings and shock absorbers land use zoning evacution chutes automatic shut of gas valves fire proof elecricity line tsunami walls
repsonse
instant media alerts
coordinated response
defence troops
japan bank support
