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Seismic hazards! - Coggle Diagram
Seismic hazards!
Seismicity
Seismicity
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Scales
Mercalli scale, is descriptive
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Richter, it is a measurement from seismographic reflections, each tier is 10 time more powerful than the other
Nature
Earthquakes occur along all plate boundaries. the quake is the sudden movement of the 2 or more plates interacting with each other. Earthquakes are more impactful in poorer countries, such as Indonesia (230k), and Haiti (360k), 80% is along the ring of fire. During the movement the terrain rises or falls (that is why Japan's defences proved ineffective)
Predictability
They are detected by seismographs, giving a populace seconds to react. There was a machine which predicted the earthquake in turkey 1998 as it tracked the movement of tension along the north Antonian fault line.
Forms
The one that comes to mind first are Earthquakes. However, this can cause secondary hazards such as Tsunamis, liquefaction and landslides
Ruptures occur when the earth splits the ground, causing damage to infrastructure due to removal of their foundations.
Loose material can give way and fall, in Nepal 2015 there were more than 6 thousand of these, thankfully less than 20 died.
Subterranean water is displaced and rises upwards, this results in the soil becoming saturated, and heavy objects (cars, infrastructure) sink. In New Zealand 2011, 15k residential buildings succumbed to liquefaction
Tsunamis are caused by the plate on top of the subducting plate springing up due to a loss of friction, this displaces water causing a big wave.
Possible Impacts are as followed: Damage to infrastructure (transport links - reduces response time, Buildings - result in homelessness). Death or injuries to humans. Education systems shutdown. reduction of law enforcement.
Possible Mitigation are as followed: Cross-bracing buildings (JPN). Buildings which are disconnected from the ground (LA emergency center). Automatic shutoff of gas pipes or nuclear reactors. Education drills (Sept 1st JPN). Sea walls to protect city from tsunami (JPN). Land use planning, moving important infrastructure away from hazardous areas.
Some responses are as followed: temporary shelter, search parties, trained and professional emergency services