maximum of 3 in a group for the poster assignment. mounted in the meeting place: people will walk around & ask questions. graded on a couple of questions & presentation. 2 types of crust: oceanic crust is denser & wants to sink down, back into the plastic rock underneath, that"s why we have oceans. Ocean floors are always/slowly sinking: continental crust is thicker, but more buoyant like an iceberg as it floats on the mantle (less dense) ic discontinuity. asthenosphere: means weak spear, weak hot plastic. plate movement: crust + asthenosphere moving together. maximum depth drilled: 12km deep, expensive and difficult to drill deeper. deepest mine is 4km down in south africa, diamond mine: any deeper is not possible: too hot. earth quakes pros: they generate energy, can be used to locate the location of plates. faults are no more than a crack in the crust.