A Worksheet on Magmatism and Earth’s Internal Heat (Week 3) INTRODUCTION TO USERS: Another week, another goal. Let today the start of something new. Welcome to your third worksheet in Earth and Life Science! Last meeting, you learned about the physical and chemical characteristics of minerals, rock-forming minerals, and the three types of rocks. In this worksheet, you'll learn where the Earth's internal heat is coming from and the formation of magma. Once you encountered a problem with this module, feel free to contact me. Developer: Ruth D. May-os (09103009599, ruth.mayos@deped.gov.ph), SSTI, Atok-District LEARNING AREA: Earth and Life Science 11 QUARTER: One MOST ESSENTIAL LEARNING COMPETENCY: At the end of this module, you should be able to: o describe where the Earth’s internal heat comes from (S11/12ES-Ib-14); o describe how magma is formed (magmatism). INTRODUCTION TO THE LESSON: Review: Recall, find, and encircle 15 concepts or terms that you encountered in your second module. Last meeting, you learned that igneous rocks are formed from solidified magma or lava but have you asked yourself, "Where are this magma coming from?" or "how are they formed?". Also, you learned that magma is a hot, liquid material. Where do you think did this hot temperature originated? Discussion: We all believe that the sun is the primary source of light and heat energy on Earth. But, do you know that aside from the sun, one source of heat energy is from the interior part of the Earth? Where is this internal heat coming from, and how are they being released on the Earth's surface? 1 SOURCES OF THE EARTH’S INTERNAL HEAT There are two main sources of the Earth's internal heat, the primordial heat, and the radioactive heat. Based on a study conducted in Japan by Itaru Shimizu, a particle physicist at Tohoku University, and his colleagues, 54% of the Earth's internal heat reaching the Earth's surface is from radioactive heat. The rest is from primordial heat. Earth's Internal Heat(%) Radioactive Heat Primodial Heat A. Primordial Heat - This is an accumulated heat released or formed during the early stages of the Earth’s formation. There are two categories of primordial heat based on the source and period of heat production. These are accretional heat and gravitational release. a. Accretional heat - - This was produced during the accretion stage of the Earth's formation. In this early stage, atoms and particles were sticking together, forming larger particles. As these larger particles gently collide with each other, they started to create more massive balls until a planetesimal was formed. Planetesimals are large or massive enough to possess gravity. Its gravity causes it to attract smaller objects. At this point, the planetesimal was being bombarded by comets, asteroids, etc. Influenced by other processes, this planetesimal evolved to a planet. The accretional heat was released during particle collisions and Earth's https://planethunters.files.wordpress.co planetesimal or protoplanet bombardment. How? m/2014/01/accretion-nature.jpg During the collision process, the Earth heats up because of the kinetic energy of the colliding bodies. This kinetic energy is converted to heat. If two meteorites collide, the heat radiates back into space. But if the collision involves a planetesimal, the energy deeply penetrates that allows heating beneath the planetesimal's surface. The debris during the collision blankets or covers the planetesimal's surface, retaining the heat inside of it. The amount or percentage of heat release during accretion is unknown because of factors such as it being dependent on environmental conditions and specific formation timescales. * The scenario is similar: hitting a hammer on a hard surface. After the hitting, the hammer heats up. The kinetic energy is transformed to heat energy. b. Gravitational release - During the formation of planetesimals and protoplanet (differentiation process), the gravitational potential of dense materials (metals) is converted to heat. In this process, the materials that compose a planetesimal or protoplanet separates according to their density. Materials or components with the highest density (iron) are moved at the center or core, while materials with the lowest density are moved at the surface. This movement of materials or components with high density creates friction and releases heat (1,000 K (1,800 °F; 1,000 °C). The amount of heat energy released is explained by the formula (E = - G M m / r) where: 2 http://www.indiana.edu/~geol105/i mages/gaia_chapter_3/earthdiff2.jpg E= Energy; G= Gravitation force; M and m = Masses of the two involved objects; and r= distance from the center Based on what was already discussed, some of the Earth's internal heat is a leftover from the Earth's formation. But, the Earth is cooling slowly. However, through another process called radioactivity, the Earth's internal temperature = is almost constant because the radioactive process is releasing almost the same heat that the Earth is losing. B. Radioactive heat - These are heat produced from four radioactive isotopes found in the Earth’s core or mantle. These are the K40, Th232, U235, and U238. Potassium-40 (K40) has a half-life of 1.28 × 109 years. Thorium-232 has a half-life of about 14 billion years. Uranium-235 half-life is over 700 million years while U238 has over 4.5 billion years. Thus this radioactive isotopes can supply parts of our Earth’s internal heat for billions of years. Estimated Earth’s Internal Temperature Inner Core Outer Core Mantle 9,000 and 13,000 degrees Fahrenheit (5,000 and 7,000 degrees Celsius) 7,200 to 9,000 degrees Fahrenheit (4,000 to 5,000 degrees Celsius) 1000° Celsius (1832° Fahrenheit) near its boundary with the crust, to 3700° Celsius (6692° Fahrenheit) near its boundary with the core EARTH’S REDISTRIBUTION OF HEAT a. Convection - The sinking of denser or colder liquid material and the rising of hotter or lighter liquid material within the mantle and outer core. b. Conduction - It is the transfer of heat from the core to the mantle or the asthenosphere to the crust. It also happens between the solid inner core and the liquid outer core. c. Radiation - It is the transfer of heat from the crust to things on the Earth's surface through the atmosphere or electromagnetic waves. d. Advection - It is the horizontal transfer of heat through fluid flow. Its difference with convection is that this is not dependent on density differences, but an external or outside force is needed for the transfer to occur. Examples of these outside forces are wind or currents. MAGMATISM Since we are done discussing the sources of the Earth's internal heat, let us move on to magma production or formation in the Earth's mantle and the rising or movement of magma towards the Earth’s crust. What is Magma? - Magma is a hot liquid material and semi-liquid rock that mostly compose the Earth’s mantle. It is composed of different minerals with a small percentage of dissolved gasses such as carbon dioxide, water vapor, and sulfur. 3 Three types of Magma according to Chemical Composition a. Basaltic Magma/Mafic Magma - It is composed of silicon dioxide, and a high percentage of iron, calcium, magnesium, and a low percentage of silicon dioxide. Its temperature is ranging from 10000C to 12000C. b. Andesitic Magma - It has a moderate amount of silicon dioxide, iron, calcium, magnesium, and silicon dioxide. Its temperature is ranging from about 800oC to 1000oC. c. Rhyolitic magma - It contains a high percentage of sodium and potassium, but a low percentage of magnesium, iron, and calcium. It has a temperature ranging from 650oC to 800oC. Formation of Magma during the Earth’s Formation - When was the formation of magma started? When there was enough primordial heat during the Earth's accretion and differentiation, the Earth's protoplanet's near-surface started to melt, forming a magma ocean. According to the most accepted terrestrial model, extensive heat from the combination of primordial and radioactive heat formed a vast magma ocean covering the Earth's surface. As the Earth cooled, the upper part of the magma ocean crystallized, forming the Earth's crust while it's lower part remained as hot, liquid magma. The pressure and high temperature inside the Earth's crust keep the magma in its liquid state. As the mantle temperature increase due to radioactivity, it causes a more significant upper mantle melting. This results in the release of more magma on the Earth's surface, forming thicker crusts. Special conditions required for the Formation of Magma 1. Decompression melting (reducing pressure at a constant temperature) - A low-pressure area has a lower melting point than a high-pressure area. Magma formation through decompression melting usually happens when a solid mantle melts as it rises to an area with lower pressure through a convection process. The melting occurs because of decompression or the reduction of pressure. 2. Flux melting ( melting of rocks due to the addition of volatiles) - Hot solid rocks usually melt, forming magma, at a lower temperature when added to a volatile substance such as carbon dioxide and water. Volatiles can decrease a rock's melting point and break the chemical bonds in a rock. This happens in subduction zones where water overlying a subducting seafloor lowers the melting point of the mantle. This melts parts of the mantle, generating magma that rises to the subduction zone surface. 3. Heat transfer melting - This happens when rock melts as it encounters a rising magma. 4 ACTIVITY 1: IDENTIFYING TERMS Instructions: Complete the term on each item's right side by identifying what is being defined or described. 1. happens when a part of solid mantle melts as it rises to an area with lower pressure 2. type of magma with a moderate amount of silicon dioxide, iron, calcium, magnesium, and silicon dioxide. 3. melting of rocks due to the additon of volatiles 4. 5. 6. 7. 8. 9. type of magma with high percentage of sodium and potassium transfer of heat between liquid and solid or solid and solid accumulated heat released during the early stages of the Earth’s formation horizontal transfer of heat through fluid flow transfer of heat within liquid or gases with different density or temperature heat produced between the collision of smaller objects and the Earth’s protoplanet 10. heat produced during the differentiation process of Earth's components 11. hot liquid material and semi-liquid rock that mostly composes the Earth's mantle 12. primordial heat produced by Uranium, Potassium, and Thorium isotopes 13. type of magma with high percentage of iron, calcium, and magnesium 14. transfer of heat through electromagnetic waves 15. Solidified Magma __ __ c __ m__r__ss__ __ n m__ l__ __ __ g a__ __ e__ i__i__ __ a__ __ a __ __ ux __ __lt__ng r__ y__l__t__ __ m__ __ m__ __ __ n__ __c__ __ o__ __ r__ __ o__ __a__ __ __a__ __ __ __ e__t__ __n __ o__ v__ __t__ o__ a__ c__r__ __ io__ __l h__ __ __t __ __ __vi__ __ t__ __n__ __ r__ __ __ a__e __a__ __ a __ __ ___ i__a__ __ i__e h__ __t __ __ s__ __t__c m__g__ __ r__ d__ __t__ __n __ a__ a ACTIVITY 2. CONCEPT MAPPING Instruction: Using a concept map, do what is being asked in each item. A concept map is a visual representation of information. It could be through graphic organizers, charts, flow charts, tables, timelines, or Venn diagrams. Use a separate sheet of paper and make sure to attach it to this worksheet. *note: Paraphrase answers. Don't copy the exact description or explanation in your worksheet. But, make sure that the content is still the same. 1. 2. 3. 4. Identify and shortly explain or describe the sources of the Earth's internal heat Identify and differentiate the three types of magma In a diagram, explain the different ways of how magma is formed. In a diagram, explain the five Earth’s internal heat transfer ACTIVITY 3: APPLICATION Electromagnetic field, gravitational force, and habitable crust existed because of the Earth's internal activity, such as the movement of hot molten materials in the Earth’s core and mantle (magma). What do you think would happened once the source of the Earth's internal heat is gone or consumed? __________________________________________________________________________________________________ __________________________________________________________________________________________________ __________________________________________________________________________________________________ What do you think is the possible alternative that science could develop or discover once the Earth nearly loses its internal heat source? __________________________________________________________________________________________________ __________________________________________________________________________________________________ __________________________________________________________________________________________________ 5 ACTIVITY 4: GENERALIZATION Give at least five importance of the Earth's internal heat. ACTIVITY 5. ASSESSMENT 1. Which among the following best describes a radioactive heat? a. heat produced by beta, gamma, and alpha decay b. heat produced by isotopes c. heat produced from molten magma d. heat from the decay of radioactive isotopes 2. Which among the following describes primordial heat? a. accumulated heat released during the early stages of the Earth’s formation b. heat produced during the accretion stage of the Earth's formation c. heat released during the differentiation of planetesimal's component d. a,b, and c 3. liquid-liquid is to convection as gas to gas is to _______________ a. Convection b. Conduction c. Radiation d. Advection 4. Magma is formed when rock melts because it is moved to a lower pressure area but with the same temperature. a. Decompression melting b. Flux melting c. Heat transfer melting c. Subduction 5. liquid-liquid is to convection as liquid to solid is to _______________ a. Convection b. Conduction c. Radiation d. Advection 6. Magma is formed when a hot solid rock is subjected to volatile substances. a. Decompression melting b. Flux melting c. Heat transfer melting d. Subduction 7. Magma is formed when rock melts because it encounters a rising magma. a. Decompression melting b. Flux melting c. Heat transfer melting d. Subduction Label the convection, conduction, and radiation below. 6 ACTIVITY 6: ADDITIONAL ACTIVITIES Optional To further enhance your knowledge about magmatism, you may click the links below and watch the sources of internal heat, magma formation, and the planet formation since it is connected to our topic. https://youtu.be/WtSE1svxRm4 https://youtu.be/FYheqR5R3QI https://youtu.be/uHUTbq-j0UU Answer Key 1. 2. 3. 4. 5. 6. 7. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. d d a a d b c Decompression melting Andesitic magma Flux melting Rhyolitic magma Conduction Primordial heat Advection Convection Accretional heat Gravitational release Magma Radioactive heat Basaltic magma Radiation Lava Activity 1 Assessment 7 REFERENCES Book Aileen C. Dela Cruz et. al., Earth and Life Science, Quezon City, EC-TEC Commercial, 2016, 24-39 Website https://www.nature.com/articles/srep02762 https://opentextbc.ca/geology/chapter/3-2-magma-and-magma-formation/ https://www.geol.umd.edu/~jmerck/geol212/lectures/10.html https://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/accretionalheating#:~:text=accretional%20heating%20The%20heating%20of,%22accretional%20heating%20.%22 http://astronomy.nmsu.edu/kurt/Astronomy110G/Lectures/18.Origins-I.pdf https://www.britannica.com/place/Earth/Effects-of-planetesimal-impacts https://physics.info/gravitation-energy/ https://earthsky.org/earth/what-is-the-source-of-the-heat-in-the-earths-interior https://www.livescience.com/15084-radioactive-decay-increases-earths-heat.html https://www.purdue.edu/science/science-express/labs/labs/Lisa-Christine%20K40%20halflife.doc#:~:text=The%20beta%20decay%2Felectron%20capture,1.19%20%C3%97%201010%20years https://www.atsdr.cdc.gov/phs/phs.asp?id=658&tid=121 https://www.sciencemag.org/news/2011/07/earth-still-retains-much-its-original-heat https://www.nationalgeographic.org/encyclopedia/magma/#:~:text=Magma%20is%20extremely%20hot%20liquid,pl anet's%20mantle%20consists%20of%20magma https://www.intechopen.com/books/earth-crust/introductory-chapter-earth-crust-origin-structure-composition-andevolution https://www.nationalgeographic.com/science/earth/surface-of-the-earth/earths-interior/ https://www.nationalgeographic.org/encyclopedia/mantle/ https://www.nationalgeographic.org/encyclopedia/magma/#:~:text=There%20are%20three%20basic%20types,low% 20in%20potassium%20and%20sodium. https://www.nationalgeographic.org/article/magma-role-rockcycle/#:~:text=Flux%20melting%20occurs%20when%20water,also%20occurs%20around%20subduction%20zones. 8