The Mohorovicic discontinuity is to be found between the earth’s crust mantles. Mohorovicic was a famous Croatian scientist a seismologist. He specialized in the composition of the earth, and particularly in earthquakes and in faults in the structure of the earth, which are the cause of earthquakes. Mohorovicic made up a series of layers rather like an onion. There are many of these layers all of different materials and all in a different state of development. The main layers are called the crust, the mantle, the liquid core and the solid core. The great pleasure inside the earth force the weaker areas of the rocky layers out of alignment and this pushing; twisting movement is experienced as an earthquake on the surface.