Changes

[[Atheism|Atheist]]ic [[scientist]]s often claim that earthquakes are caused by [[plate tectonics|tectonic]] activity in an area after the release of stored [[energy]] from the [[rock]]. But, in fact, earthquakes often do not occur on tectonic plate boundaries or [[fault]]s where previous movement has occurred. There are currently 500,000 detectable earthquakes in the world each year.  

[[Atheism|Atheist]]ic [[scientist]]s often claim that earthquakes are caused by [[plate tectonics|tectonic]] activity in an area after the release of stored [[energy]] from the [[rock]]. But, in fact, earthquakes often do not occur on tectonic plate boundaries or [[fault]]s where previous movement has occurred. There are currently 500,000 detectable earthquakes in the world each year.  

Earthquakes are a significant [[natural disaster]] to [[population]]s living in areas prone to them, and emergency responses to the hazard vary with [[economic]] development. The most powerful and destructive earthquakes occur at tectonic plate boundaries like the [[San Andreas Fault]].

Earthquakes are a significant [[natural disaster]] to [[population]]s living in areas prone to them, and emergency responses to the hazard vary with [[economic]] development. A myth perpetuated by [[Old Earth]]-believers is that the most likely place for an earthquake is in proximity to tectonic plate boundaries like the San Andreas Fault.  In fact, many major earthquakes occur nowhere near a large fault line.

The severity of earthquakes is measured using the Moment Magnitude scale, which replaced the [[Richter scale]] in the 1970s. The largest quake ever recorded had a magnitude of 9.5; it struck [[Chile]] in 1960.<ref>http://earthquake.usgs.gov/earthquakes/world/10_largest_world.php</ref> Technically the Moment Magnitude scale only measures the absolute magnitiude; the [[Mercalli scale]] is used to measure the felt magnitude - essentially how much the ground shakes over the [[epicenter]] of the quake.

The severity of earthquakes is measured using the Moment Magnitude scale, which replaced the [[Richter scale]] in the 1970s. The largest quake ever recorded had a magnitude of 9.5; it struck [[Chile]] in 1960.<ref>http://earthquake.usgs.gov/earthquakes/world/10_largest_world.php</ref> Technically the Moment Magnitude scale only measures the absolute magnitude; the Mercalli scale is used to measure the felt magnitude - essentially how much the ground shakes over the [[epicenter]] of the quake.

==Causes of Earthquakes==

==Causes of Earthquakes==

Where tectonic plates are moving relative to each other, stress is created as friction prevents the edges of the plates from moving smoothly. When the stress has increased enough to overcome the friction, the plates will release the stored energy by moving abruptly, causing an earthquake.

Where tectonic plates are moving relative to each other, stress is created as friction prevents the edges of the plates from moving smoothly. When the stress has increased enough to overcome the friction, the plates will release the stored energy by moving abruptly, causing an earthquake.

'''Intra-Plate Earthquakes'''

'''Intra-Plate Earthquakes'''

Large movements of plates may cause stress zones that extend far from the boundaries. When this stress includes a weak area in the plate - known as a fault - the fault can release energy by slipping abruptly, again causing an earthquake.

Large movements of plates may cause stress zones that extend far from the boundaries. When this stress includes a weak area in the plate - known as a fault - the fault can release energy by slipping abruptly, again causing an earthquake.

'''Vulcanism'''

'''Vulcanism'''

The movement of magma within [[volcano]]es can induce earthquakes. These are often an indicator of an approaching eruption, as at [[Mount St Helens]].

The movement of magma within [[volcano]]es can induce earthquakes. These are often an indicator of an approaching eruption, as at [[Mount St. Helens]].

 

==Earthquakes and a young Earth==

==Earthquakes and a young Earth==

Severe earthquakes have doubled every forty years.<ref>[http://www.science-frontiers.com/sourcebk.htm#Geology Geological Catalogs] (Science Frontiers)</ref> If the planet was not young, it would be completely unstable. See [[Counterexamples to an Old Earth]].  

Severe earthquakes have doubled every forty years.<ref>[http://www.science-frontiers.com/sourcebk.htm#Geology Geological Catalogs] (Science Frontiers)</ref> If the planet were not young, then it would be completely unstable by this time. See [[Counterexamples to an Old Earth]].  

 

 

[[File:Japan quake World latest USGS - PD.jpg|550px|left]]

[[File:Japan quake World latest USGS - PD.jpg|550px|left]]