The geosphere is the rocky layer of the earth. The first layer is the crust and is 5-10 km. below the oceans, and 20-70 km.below the continet. The second layer is the mantleand that is about 2900 km. thick.The third layer is the outer core, and that is about 2250 km. thick.The fourth layer and the final layer is the inner core and is about 1280 km. thick.