Lesson 6: The Earth's Internal Heat PDF

LESSON 6: THE EARTH’S INTERNAL HEAT EARTH AND LIFE SCIENCE - 11 LEARNING OBJECTIVES After going through this module, you are expected to: 1. Describe the parts and function of Earth’s interior. 2. Describe where the Earth’s internal heat comes from. 3. Identify the sources of Earth’s internal h...

LESSON 6: THE EARTH’S INTERNAL HEAT EARTH AND LIFE SCIENCE - 11 LEARNING OBJECTIVES After going through this module, you are expected to: 1. Describe the parts and function of Earth’s interior. 2. Describe where the Earth’s internal heat comes from. 3. Identify the sources of Earth’s internal heat; namely, radiogenic heat and primordial heat. 4. Describe the processes of heat transfer in Earth’s mantle. WHAT ARE THE THREE MAIN LAYERS OF THE EARTH? ❑ CRUST ❑ MANTLE ❑ CORE (Inner and Outer) WHAT ARE THE THREE MAIN LAYERS OF THE EARTH? ❑ CRUST - Very thin layer of the earth. ❑ MANTLE - a very largest layer of the earth (1,800 miles thick) ❑ INNER CORE - composed of liquefied metals such as nickel and iron ❑ OUTER CORE - also composed of metals however they are not kept in a liquefied state WHAT ARE THE TWO MAIN SOURCES OF HEAT? ❑PRIMORDIAL HEAT ❑RADIOGENIC HEAT WHAT IS PRIMORDIAL HEAT? PRIMORDIAL HEAT - the heat left over from the formation of the Earth - the internal heat energy that gradually gathered by means of dispersion in the planet during its few million years of evolution WHAT IS THE MAJOR CONTRIBUTION OF THIS INTERNAL HEAT (PRIMORDIAL HEAT)? The major contribution of this internal heat is the accretional energy – the energy deposited during the early formation of a planet. WHAT IS RADIOGENIC HEAT? RADIOGENIC HEAT - the thermal energy released as a result of spontaneous nuclear disintegration - disintegration of natural radioactive elements inside the earth – like Uranium, Thorium and Potassium. How much is the approximate terawatts in the flow of heat in earth’s interior to its surface? - 47 terawatts What is produced by the radioactive decay of isotopes in the mantle and crust? - Radiogenic Heat Why does radioactive decay play a very important role in earth’s internal heat? ✓Spontaneous nuclear disintegration of radioactive elements produced thermal energy. ✓Radioactive element can be found anywhere in the planet. ✓When radioactive element decays, it produces heat. THREE PROCESSES OF HEAT TRANSFER ❑CONDUCTION ❑CONVECTION ❑RADIATION CONDUCTION - processes happen in the earth’s surface and it directs the thermal settings in almost entire solid portions of the Earth and plays a very important role in the lithosphere. CONVECTION - is the transfer of heat by the movement of mass, and it is a more effective mode of heat transport in the Earth than pure conduction. CONVECTION IN THE MANTLE RADIATION - The process of heat exchange between the Sun and the Earth, through radiation, controls the temperatures at the Earth's surface How does the conduction in the surface of the earth affect the temperature of our atmosphere? A. Air molecules do not come in contact with the warmer surface of the land and ocean resulting to the increase of its thermal energy. B. Air molecules do not come in contact with the cooler surface of the land and ocean resulting to the increase of its thermal energy. C. Air molecules come in contact with the warmer surface of the land and ocean resulting to the increase of its thermal energy. D. Air molecules come in contact with the cooler surface of the land and ocean resulting to the decrease of its thermal energy. ANSWER: LETTER C How convection in Earth’s mantle does affect the formation of landmass like volcano and mountain? A. When warm material in the mantle rises up to the surface (ground), it will cool and sinks, these cooled materials will eventually be turned into landmass. B. Collision and separation of tectonic plates happens due to the slow motion of convection cells. C. Heat tries to escape in the interior of the earth. D. All of the above ANSWER: LETTER D ACTIVITY: FILL ME UP