Earth Structure & Plate Tectonics Notes Earth on the Move Earth Structure & Plate Tectonics Notes Another Fabulous Mr. K Presentation
Another Fabulous Mr. K Presentation Earth, Inside & Out The Earth is divided into three layers Crust Mantle Core Another Fabulous Mr. K Presentation
Another Fabulous Mr. K Presentation Crust (1) This is the outermost layer of the Earth. (2) This is the layer we walk on. (3) It is a thick, rocky skin. (4) If we think of the Earth as a billiard ball, this crust is as thin as a postage stamp stuck on a billiard ball. (5) At its thickest, which is under mountain ranges, the crust is only about 35km (22mi) thick. Another Fabulous Mr. K Presentation
And what type of crust would you like with your Earth? There are two types of crust Another Fabulous Mr. K Presentation
Another Fabulous Mr. K Presentation Continental Crust: 1. Makes up the continents 2. Contains light colored rocks such as granite. 3. Floats high on the mantle Another Fabulous Mr. K Presentation
Another Fabulous Mr. K Presentation (i) Oceanic Crust 1. Makes up the ocean floor 2. Contains the dense rocks such as basalt Thinner than the continental crust Another Fabulous Mr. K Presentation
Another Fabulous Mr. K Presentation Mantle (1) Hotter and denser than the crust because the deeper you go inside the earth, the temperature & pressure increases. (2) Made of solid rock. The Mantle is made of two zones Another Fabulous Mr. K Presentation
Another Fabulous Mr. K Presentation Mantle Zones (a) Lithosphere (i) Thin, uppermost part of the mantle; cooler & less rigid (ii) Floats on the athenosphere, and slides around very slowly. (iii) The upper part of the lithosphere melts rocks, forming a substance called magma. Another Fabulous Mr. K Presentation
Another Fabulous Mr. K Presentation Magma 1. Magma (melted rock) moves like hot oatmeal. Uneven heating causes material in the mantle to constantly and slowly rise & fall in convection currents. Convection Current: process by which hot fluid rises to the surface, and then sinks again, like soup being heated in a saucepan Another Fabulous Mr. K Presentation
Another Fabulous Mr. K Presentation (a) Asthenosphere Hot, weak zone directly under the lithosphere Flows at a very slow rate Another Fabulous Mr. K Presentation
Another Fabulous Mr. K Presentation Core i) Deep within the Earth is the core ii) The core is made mostly of nickel & iron iii) Twice as dense as the mantle. Main source of heat that triggers the convection currents Another Fabulous Mr. K Presentation
The core is made of two layers (1) Outer core: molten & is responsible for the Earth’s magnetic field. Inner core: solid Another Fabulous Mr. K Presentation