EESA06H3 Lecture 1: EESA06- Lecture 1
Document Summary
There is nowhere that is stable on the earth"s surface (moving. Na moving 3. 7cm a year towards south west horizontally and vertically) 400 million years ago toronto was at the equator. Movement of earth is not random continents apart. Supercontinents- unstable, they break up (is a cycle) Outcrops- when you can see rocks in a field. Vector- shows the rate and direction of movement. Rocks- can behave like elastic material, can be bent. Heat builds up under supercontinent (because it traps it) and causes a rebound which tears apart the supercontinent- creating new oceans. Oceans are widening (sea floor spreading)- pushes the. Reaches a thickness where it gives up and sinks into the soft rock of the mantle (subduction)- that"s where earthquakes and tsunamis happen. 3. 5 billion age of the first continent. Arc of caribbean island- identify a seduction zone. Silica- if you add it to a magna it stiffens it.
