reply to post by minkey53
363 miles?? under sea?
im no expert, but im sure you have a point their!
(i remember posting about crust depths before, ill go look it up ...check my work and ect)..
i couldnt find my previous post, but i got the basics from wiki .... i knew 363 miles seemed a bit weird...
The structure of the Earth can be defined in two ways: either chemically, or by mechanical properties such as rheology. Mechanically, it can be
divided into lithosphere, asthenosphere, mesosphere, outer core, and the inner core. The interior of the earth is divided into 5 important layers.
Chemically, Earth can be divided into the crust, upper mantle, lower mantle, outer core, and inner core. The geologic component layers of Earth[1] are
at the following depths below the surface:
Depth Layer
Kilometers Miles
0–60 0–37 Lithosphere (locally varies between 5 and 200 km)
0–35 0–22 … Crust (locally varies between 5 and 70 km)
35–60 22–37 … Uppermost part of mantle
35–2890 22–1790 Mantle
100–200 62–125 … Asthenosphere
35–660 22–410 … Upper mantle
660–2890 410–1790 … Lower mantle
2890–5150 1790–3160 Outer core
5150–6360 3160–3954 Inner core
(TAKEN FROM
en.wikipedia.org... )
just to add, if i remember right, the earths crust goes as thin as 1-2 miles at parts, under very deep ocean.
now, this quake... in the upper mantle?? i never even knew that was possible! i thought the tectonic plates floated on the liquid mantle ?!?
edit edit: im posting on the fly.. just done some searching on quakes that deep ... and got some interesting stuff on a previous set of series of
events(quakes @ >30km depth) in the sameish area, (ill let the experts decide .. im no expert)
Abstract
We present analyses of two swarms of long-period (LP) earthquakes at > 30 km depth that accompanied the geodetically observed 2002–2005 Mauna Loa
intrusion. The first LP earthquake swarm in 2002 consisted of 31 events that were precursory and preceded the start of Mauna Loa inflation; the second
LP swarm of two thousand events occurred from 2004–2005. The rate of LP earthquakes slowed significantly coincident with the occurrence of the
December 26, 2004 Mw 9.3 Sumatra earthquake, suggesting that the seismic waves from this great earthquake may have had a dynamic triggering effect on
the behavior of Mauna Loa's deep magma system. Using waveform cross correlation and double difference relocation, we find that a large number of
earthquakes in each swarm are weakly similar and can be classified into two families. The relocated hypocenters for each family collapse to compact
point source regions almost directly beneath the Mauna Loa intrusion. We suggest that the observed waveform characteristics are compatible with each
family being associated with the resonance of a single fluid filled vertical crack of fixed geometry, with differences in waveforms between events
being produced by slight variations in the trigger mechanism. If these LP earthquakes are part of the primary magma system that fed the 2002–2005
intrusion, as indicated by the spatial and temporal associations between mantle seismicity and surface deformation, then our results raise the
possibility that this magma system may be quite focused at these depths as opposed to being a diffuse network. It is likely that only a few locations
of Mauna Loa's deep magma system met the geometric and fluid dynamic conditions for generating LP earthquakes that were large enough to be recorded
at the surface, and that much of the deep magma transfer associated with the 2002–2005 intrusion occurred aseismically.
www.sciencedirect.com...
084528973&_rerunOrigin=google&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=060d6434d94516fa99403170bcab95cc
[edit on 9-11-2009 by boaby_phet]
