Subduction at Tonga

This is a 3D visualization of the Tonga subduction zone in the South Pacific. The subducting oceanic crust is blue and earthquakes are colored cubes. The red pyramid marks the epicenter of a magnitude 8.0 earthquake that happened on May 3 2006. The Tonga subduction zone is the most seismically active region on Earth.

The structure of the subsurface was created by analyzing the sounds that earthquakes make, this is the science of seismic tomography. The same principal is used in ultrasound imaging, just that the wavelength of the sound waves is much longer in earthquakes 5 to 15 Hz compared with 200,000 Hz in ultrasound imaging.

The 3D visualization was created by the SIO Visualization Center at the Scripps Institution of Oceanography. Data and imagery is free for educational purposes, so long as you read the following Legal Disclaimer:

http://siovizcenter.ucsd.edu/library/objects/MBARI_readme.txt

Category:

Film & Animation

Tags:

• earthquake
• subduction
• Tonga
• trench
• geology
• seismic
• epicenter

[oicurageologist]

That is a great demonstration of the earthquakes along the plate boundary, Is it possible to use beachballs instead of boxes? using size for magnetude and showing relative directions? Just curious.

[Diamonddavej]

I'm sure it is possible, and a web search may find such an animation, you should read about InSar.

[Diamonddavej]

@adkinsjr The colours represent the speed that seismic waves (earthquake sounds) travel though the Earth, the denser the rock the faster seismic waves travel. Blue areas are cold denser oceanic lithosphere (faster seismic waves), whereas yellow & red areas are hotter less dense mantle (slower seismic waves).

Also, samples of rock from the sea-floor & xenoliths erupted in volcanoes (mantle Peridotite) can be examined & seismic velocity measured, confirming the seismic profile seen here.

[adkinsjr]

@Diamonddavej

"They have samples of the rocks from the subduction zone, the rocks collected confirm the seismic pictures and Plate Tectonics."

That sounds interesting, could you explain further though? How exactly do they confirm the seismic pictures? I'm not a deniar of plate techtonics or anything, I'm just curious...

[Diamonddavej]

@aztecking21122012 1. Oil industry uses seismic surveying to find oil and gas reserves.

2. NanTroSEIZE is a project that successfully drilled into the Nankai Trough Subduction Zone zone, enter "IODP Exps. 314, 315, 316" into youtube search.

3. The giant the Japanese drilling vessel Chikyu, NanTroSEIZE project, drilled into the Nankai Trough Subduction Zone. They have samples of the rocks from the subduction zone, the rocks collected confirm the seismic pictures and Plate Tectonics.

[aztecking21122012]

@Diamonddavej If we could see 500km into the earth, then oil exploration would not be necesary. This video is then only an artist rendition and the portion to support subduction is added falsly.

[aztecking21122012]

@judgegixxer Well I'm an idiot too then, because i do not see how this video proves subduction. I am in agreement with the EE theory as even Darwin proposed it, and Einstein. To say abosolutely one way or the other is not scientific. You have stated an absolute, this cannot possibly be true. Why can't the earth expand and have FOLDING of the plate edges instead of subduction. It seems to me this is just as reasonable a theory and this video even would support it.

[aztecking21122012]

Nice animation that still does not prove subduction. I have yet to see a single photogragh of a subduction zone. I have seen hundreds of expansion zone photos but not one of subduction. Why is that I wonder. But there certainly a lot of animations!

[johannesvalks]

COOL!

greetings