In this section i am going to be talking about the structure of the earth, so lets get started. The earth has a lot of layers like cores inner and outer, lower mantle and the asthenosphere, the oceanic crust and the continental crust, and atmosphere is the air that surrounds us, all the layers have its on functions that benefit the earth the cores inner and outer creates a magnetic field that protects the earth from radiation the suns heat waves, the lower mantle creates convectional currents that make the plates move, the asthenosphere is what the plate moves on and the plates move 3 cm a year, the oceanic crust creates divergent boundaries and creates new crusts, the continental crust is what we and standing on it was created millions of years ago and it is the existence of life, and finally the atmosphere is the air that we breath and it gives the plant matter life it keeps the air trapped. the layers of the earth creates earthquakes happen due to the plates colliding, so lets talk about the plates now. their are a lot ways the plate moves there is the divergent boundary, the convergent, and the transform boundary, and the continental drift theory that Alfred Wegener created he said that the continental drift the movement of the earths splitting he said western Africa and eastern south america looked like they connected together like a jigsaw puzzle. divergent boundaries are the plates separating but as the plates separate they create a fault crack in the middle and that is called rift valleys. transform boundaries are plates sliding past each other so no cracks or crunches are formed in the surface but signs are let not serious signs. convergent boundaries are plates colliding at each other but the plates only move a few cm a year so the collision process is very slow. their are four time eras Cenozoic (recent life) which is between 66 million years age till now, Mesozoic (middle life) which is between 245-66 million years ago, Paleozoic (ancient life) which is between 570-245 million years ago, and finally precambrian (earliest life) which is between 4600-570 million years ago.