– photos of the uplifted coastline from the earthquake in Chile.
“Earlier this year, the 8.8 quake that hit Chile did more than level homes. It raised the ocean floor so much that undersea regions broke the surface of the water. Here are pictures of Chile’s incredible new coastline.”
subduction zones when locked can deform the overriding plate and when the stress is released the plate “slaps” back down, and other places rise up. depends on where in the bulge you are! there are drowned forest on the coast of Washington from the last release in the Juan de Fuca subduction zone, that area dropped enough for salt water to get into the roots and kill the tress. Same thing happened in the ’64 quake in Alaska. However its not all dropping. closer in you can get uplift. Think of it this way, if you take a ruler and push down on one end, you get a depression but a little further back it buckles up into a hump. so when that stress is released part goes up (back to original position) and part goes down (back to original position). These coastlines in Chile went up! I hope that made sense. Its the same physics in both cases the uplift and down dropping.
though not mentioned much in the write ups on this study I believe that, this study is looking at a low velocity zone in the earth and inferring that the edges of these large low velocity zones are where you get mantle plumes, and that in order to get diamonds on the surface you need something like a mantle plume to punch through the whole crust and bring them up. On the next podcast I am going to talk about earth structure and a little bit about seismology and how it was used to determine earths structure. the map is a map of % changes in velocities of seismic waves (how we map things we can’t see) I am pretty sure there was something on this in one of my other podcasts I listen to so I’ll find it and post a link below!