EARTH’S INTERNAL STRUCTURE 1 - Earth structure & dimensions 2 - Layers of the earth 3 - Elements of the earth

Earth structure & dimensions Earth is a terrestrial planet Terrestrial planet : one of the first four planets of the solar system whose surface is composed of solid rock. The radius of the Earth is approximately 6400 km

Layers of the earth The Earth is composed of the following layers : 1) The Crust 2) The Mantle - The upper mantle (or asthenosphere) - The lower mantle 3) The Core - The outer core - The inner core

Layers of the earth The Crust Upper Mantle Lower Mantle Outer Core Inner Core

Layers of the earth LAYER DISTANCE TEMP. CRUST 5 – 65 km 5˚ C UPPER MANTLE 670 km 1000˚ -1800˚ C LOWER MANTLE 2885 km 1800˚ - 3700˚ C OUTER CORE 2270 km 3700˚ - 4500˚ C INNER CORE 1216 km +4500˚ C

Layers of the earth

Layers of the earth: THE CRUST The solid surface of the Earth is called the crust. The Terrestrial crust covers the other layers of the Earth. It becomes warmer and warmer as it approaches the center of the Earth

Layers of the earth: THE CRUST The Earth's crust is solid. Its thickness varies: between 5 and 10 km under the oceans (oceanic crust) between 30 and 65 km under the continents (continental crust)

Layers of the earth: THE MANTLE THE MANTLE is directly beneath the Earth's crust. Its temperature is much hotter than the Earth’s crust and is hotter in the lower mantle than the upper mantle (or asthenosphere). UPPER MANTLE - Asthenosphere Its thickness can reach 670 km. This layer is semifluid. It consists of partially molten rock. It is believed that this is the surface on which the tectonic plates move (the movement of continents).

Layers of the earth: the mantle LOWER MANTLE This layer is solid despite its high temperature because the pressure is too strong. It consists mainly of silicon , oxygen , iron and magnesium.

Layers of the earth: the core THE CORE is located below the two layers of the mantle. THE OUTER CORE is liquid. The metal elements in this layer gave rise to Earth's magnetic field. Its thickness is about 2.270 km . THE INNER CORE Despite its very high temperature, it is solid due to the pressure.

Elements of the earth During the birth of the Earth, the heavier elements , like Iron (Fe) and Nickel (Ni), were attracted towards the center of the Earth and formed the nucleus. The lighter elements , such as Silicon (Si) , Oxygen (O) and Aluminum (Al), have come together on the surface of the Earth to form the mantle and crust.

EARTH = THE EGG One can compare the internal structure of the Earth to that of an egg. The shell is the crust The White is the mantle The core is yellow

EARTH = THE EGG CRUST SHELL MANTLE EGG WHITE CORE YOKE