Japan-Mariana arc by Caitlin Hall https://padlet.com/caitlinmhall/3dpnzamzbzrx Made with an aura of mystery en-us 2018-03-15 01:31:24 UTC 2025-01-31 20:04:12 UTC hello@padlet.com https://padlet-assets.s3.amazonaws.com/icons/Ninja.png Structure of the subduction zone and where is it active? caitlinmhall https://padlet.com/caitlinmhall/3dpnzamzbzrx/wish/242161079  
o   The structure of the Mariana Trench, changes from steeply dipping areas to the North and South of Japan. Underneath Japan, it dips shallowly with the Earthquakes only reaching a depth of 70 km over a 328 km span.

The trench itself involves three main plates, these are the Pacific plate, the Philippine plate and the North American plate. The pacific plate decends under both plates, however the Philippine plate also subducts under the North American plate creating a triple point.

There are three main areas seen which are possible areas of locking within the trench, these are at North Japan at Hokkaido, Okhotsk Valley, just South of Russia and half way between Japan and Guam. These areas where they are locked are most likely due to large island formations causing the subduction zone to lock.

]]> 2018-03-15 01:40:15 UTC https://padlet.com/caitlinmhall/3dpnzamzbzrx/wish/242161079 Google Earth Movie portraying the subduction slab around Mariana Arc ffionrobb https://padlet.com/caitlinmhall/3dpnzamzbzrx/wish/242161229 Video attached below:]]> 2018-03-15 01:41:07 UTC https://padlet.com/caitlinmhall/3dpnzamzbzrx/wish/242161229 Determine the slab dip and draw a cross-section through two portions of it caitlinmhall https://padlet.com/caitlinmhall/3dpnzamzbzrx/wish/242161425 2018-03-15 01:42:41 UTC https://padlet.com/caitlinmhall/3dpnzamzbzrx/wish/242161425 How does our interpretation of subduction relate to surface features (and what these are) caitlinmhall https://padlet.com/caitlinmhall/3dpnzamzbzrx/wish/242162588 As the subducting slab of the Pacific Plate is subducted, a trench forms between the Pacific and the Philippine Sea/North American Plates. The deepest point of the trench (and on Earth) is the Mariana Trench, at 11km depth. Although the plate dips slowly on the surface, tectonic forces cause the plate to make a near-vertical dive to cause the deep trench.

We see island arcs chains forming in areas of ocean-ocean collision
Back arc basins and spreading ridges (esp. near Guam)

We have a plug where the Pacific plate meets the Eurasian Plate

https://maps.ngdc.noaa.gov/viewers/bathymetry/

]]> 2018-03-15 01:45:33 UTC https://padlet.com/caitlinmhall/3dpnzamzbzrx/wish/242162588 Explain what will happen in 10 million years' time caitlinmhall https://padlet.com/caitlinmhall/3dpnzamzbzrx/wish/242162707 The Pacific Plate is subducting under the Eurasian Plate and the Philippine Plate at a rate of 90 mm/yr. The high concentration of sea mounts off the west coast of Japan may slow down subduction or cause pressure to build up at the subduction interface. It is therefore predicted that the Pacific plate will move the Australian continent toward Japan.]]> 2018-03-15 01:46:29 UTC https://padlet.com/caitlinmhall/3dpnzamzbzrx/wish/242162707