The Latitude Factor in Quakes
It's the obsession of many to try to work out the why where and how of stuff. Without this human drive, researchers would never have contributed to the progression of technologies into the 21st century. But the workings of our planet are perhaps the most critical area of endeavour: quakes and natural disasters rank highly in terms of study because of the potential for catastrophic impact on people.
This Latitude analysis offers a possible factor in targeting vulnerable areas, since it is known though data that the earth is not equally susceptible in all zones.
Japan at latitude 36N
ten percent of the world's active volcanoes are found in Japan, which lies in a zone of extreme crustal instability -Geography of Japan
NZ is at latitude 41S
New Zealand straddles the boundary between two tectonic plates. The subduction of the Pacific plate under the Indo-Australian Plate results in volcanism, especially in the North Island's Taupo Volcanic Zone.
The collision between the two plates causes regular earthquakes, though severe ones are infrequent. These have uplifted the Southern Alps along the Alpine Fault... New Zealand experiences around 14,000 earthquakes a year,[4] some in excess of magnitude 7. Geography of New Zealand
This Latitude analysis offers a possible factor in targeting vulnerable areas, since it is known though data that the earth is not equally susceptible in all zones.
Japan at latitude 36N
ten percent of the world's active volcanoes are found in Japan, which lies in a zone of extreme crustal instability -Geography of Japan
NZ is at latitude 41S
New Zealand straddles the boundary between two tectonic plates. The subduction of the Pacific plate under the Indo-Australian Plate results in volcanism, especially in the North Island's Taupo Volcanic Zone.
The collision between the two plates causes regular earthquakes, though severe ones are infrequent. These have uplifted the Southern Alps along the Alpine Fault... New Zealand experiences around 14,000 earthquakes a year,[4] some in excess of magnitude 7. Geography of New Zealand
Crustal plates and volcanism tend to go hand in hand, though "hot spots" occur away from boundaries -such as in Hawaii
Huge plates dominate the planet in the extreme northern and southern latitudes and the most seismically active zone surrounds and falls within the Pacific Ocean, where huge populations live on the continental fringes of North and South America as well as the islands of Japan, Indonesia, Micronesia, Polynesia, down to the southermost nation of New Zealand, two large islands sitting astride the crustal boundary.
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| crustal plates - enlarged source: Wikimedia commons |
In fact, NewZealand, Chile, California and Japan, broadly speaking comprise the core co-ordinates of the zone - the central zones of these all falling within the latitude range 35-41 north/south of the equator.
So if this zone is significant, the question why may relate to the pull of the moon, which only travels to a maximum of 28.5 degrees north or south, crossing the equator every 2 weeks. The moon passing over the equator is significant because earth's curvature means the equator provides the closest proximity between moon and earth. This proximity is increased further when the perigee portion of the monthly moon cycle coincides with an equatorial passage. 2011 perigee tables show March and October 2011 to be closest passage. A globally significant event occurred in March ( Japan) when the moon was close to max north declination, but not close to perigee. Other factors were obviously in the mix). What is interesting to ask here is whether the pull of the moon, as it headed towards the latitude of Japan, was able to precipitate undersea seismic activity. Nothing of that impact appears evident in October 2011. Lets get through May and June first.
Update July 8, 2011
Refer to recent post on the solar minimum -and how the sun has a preferred latitude band for its sunspot activity.
