Constructive & Destructive Forces

Monster Wrangler Mike Presents Constructive & Destructive Forces Includes: anchor charts note-taking sheets reading passages with textdependent questions 12-color card sort activity 24 vocabulary word card game 6 riddles

Essential Question: What are Landforms? Land has many different shapes. Any natural (naturally occurring; not manmade) land shape is called a landform. If you were to describe the landforms in your town you would be describing the area s topography, or all the kinds of landforms in a certain area. Landform Mountains Volcanoes Hills Description A landform that is much higher than the surrounding land. Often, mountains occur in groups called ranges. Some have tall, jagged peaks like the Rocky Mountains. Others, like the Appalachian Mountains are low with gentle, rounded slopes. A volcano is just a mountain made of lava, ash, or other materials from eruptions. Unlike mountains, they occur individually instead of in ranges. Hills are similar to mountains but not as high and most have rounded versus jagged slopes. Plains Sand Dunes Barrier Islands Mesa Canyons A plain is a large, flat landform with very little difference in elevation. For example, the Great Plains in the middle of the United States -- in such states as Oklahoma -- is very flat. You can think of a sand dune as a hill made of sand that was made and shaped by the wind. As the wind blows, it moves the sand and reshapes the dune. These islands are long, narrow piles of sand that help protect the main land from wave erosion. Rather than being moved by wind, this sand is moved by the ocean waves and currents. Mesa is the Spanish word for table. It is a tall, flat-topped rock feature that was created by running water which erodes the surrounding rock. Canyons are deep valleys with steep sides found mainly throughout the Southwest United States. The Grand Canyon (Arizona) is the largest land canyon in the world. It was carved by the rushing water of the Colorado River.

Similarities and Differences Directions: Use your chart about landforms to compare and contrast different landforms and the way they were created. 1. How are volcanoes different from mountains? 2. How is a mountain similar to a hill? 3. What makes a mesa different from mountains or hills? 4. How are barrier islands and sand dunes alike? How are they different from one another? 5. Circle the one of these that is not created by rushing water canyon, mesa, sand dune, or barrier island? What creates the one you circled? 6. Which of these has little to no difference in elevation to its surrounding area plain, hill, mountain or volcano? 7. Not all mountains are created equal. How are the Rocky Mountains different from the Appalachian Mountains? Use the Venn diagram. Rocky Mountains Appalachian Mountains

Two Types of Forces in Earth s Surface Destructive Processes that destroy or tear down landforms. Examples include: Landslides Volcanic eruptions Earthquakes Floods Roots from trees Weathering Erosion Animals Constructive Processes that construct or build up an existing landform or create a new one. Examples Include: Deposition of sand by wind (dunes) or by water (deltas and sandbars). Landslides Volcanic eruptions Floods Weathering Erosion Some forces within the earth can actually be both destructive and constructive. Look at the lists above. Using a highlighter or colored pencil, highlight, underline or circle the ones that appear in both list. Then have a discussion with a partner about how you think these forces can be both destructive and constructive. Record your thoughts here:

Essential Question: What is weathering? Weathering is the process of breaking down rocks at or near Earth s surface into smaller pieces. Ouch! Heavy rains caused a flood which knocked me into other rocks breaking me apart. The wind carries these pesky bits of rock and sediment which keep pounding against me, over time chipping pieces of me away and wearing me down. After it rained the temperature dropped causing the water to freeze in my cracks. As the ice expanded it broke me apart.

Essential Question: What is weathering?

Essential Question: What is erosion? Erosion is the movement of sediments and soil by wind, water, ice, gravity, and even animals. Erosion by wind Explanation As the wind blows, it picks up rock, sediment and soil and carries it to a new location. water ice Water such as ocean waves, floods, or flowing rivers or streams pick up rock, sediment and soil and carries it to new locations. Glaciers are slow moving rivers of ice that gradually pick up rock, sediment, and soil and carry is slowly to new locations. gravity animals Gravity is the force that attracts objects toward the center of the earth. Landslides are caused by the downward pull of gravity. Even animals can cause rock, sediment and soil to move as they burrow through the ground, move across the land, or even eat plants such as grass which then loosens and moves the soil.

Essential Question: What is erosion? Erosion is the movement of sediments and soil by wind, water, ice, gravity, and even animals. Erosion by Explanation wind water ice gravity animals

Essential Question: What is Deposition? To deposit means to drop off. You might make a deposit when you drop off money at the bank into your account. After rock has been broken (weathered), and carried away (eroded), it is then dropped off in a new location (deposited). Examples of Deposition Sand dunes are the result of sand being deposited in new locations by the wind. These are common on beaches and in deserts. A delta is the resulting landform when sediment is deposited at the mouth of a rushing river where it empties into a bigger body of water such as a gulf or an ocean. Currents and waves in the ocean also carry sediment. As it begins to deposit and pile up the sediment can create a sandbar (you can think of these as underwater sand dunes). Checkpoint! 1. What forces of nature can cause deposition? 2. Knowing what you know about constructive and destructive forces, would you say deposition is constructive or destructive? Give examples from this text to support your choice. 3. Use a map to name the body of water where the Mississippi River empties. What would form at the mouth of this river? 4. Use deposit or deposition in a sentence using the context clue drop off to help clarify the meaning within the sentence.

Volcanoes A volcano is actually a mountain made of lava, ash, or other materials from eruptions. What s the difference between magma and lava? Magma is the melted, or molten rock, beneath Earth s surface, while lava is the molten rock that reaches Earth s surface. There are 3 types of volcanoes: Composite Shield Cinder Cone Wide Fairly steep slopes Alternating layers of lava and ash Mount St. Helens (Washington state) Broad Gentle slopes Lava flows easily from vents (openings in the crust) Hawaii is made of 5 different shield volcanoes Mauna Loa in Hawaii is the most massive mountain on Earth Tall Narrow Steep slopes Made of rock, ash, and other solid materials Not made of lava Paricutin in Mexico Use the clues from the chart above to write three riddles about the three types of volcanoes.

Destructive Volcanoes can be destructive forces within the earth because they can ruin buildings, knock down trees, erupt the land, break apart rocks, and kill animals and plants, Volcanoes can be constructive forces too. They can actually create new land. When the magma erupts, the lava that flows over the ground cools and hardens into a crust which later forms soil. Constructive

Earthquakes Earth s crust is broken into blocks called plates which fit together almost like puzzle pieces. These plates are always moving whether we feel them move or not. They rest, or float, on top of a layer of the Earth called the mantle. Sometimes the plates push together, sometimes they pull away from each other, and other times they slip past one another. This sudden release of energy within the Earth s crust causes the ground to move which results in an earthquake. Deep within the crust there is a place where the energy is released which is called the focus. Sometimes the energy is not even noticeable, and other times it can cause massive destruction. Just above the focus is where the most damage would occur. On the earth s surface we call this spot the epicenter of the earthquake. You might be wondering where earthquakes are likely to occur. There are breaks or giant cracks in the Earth s crust called faults which occur near the edges of the plates mentioned earlier. The San Andreas Fault is located in California where many Earthquakes are likely to happen. Although millions of earthquakes happen every year, they are often too small to be felt. However, some earthquakes measuring 6.0 or higher on the Richter scale can cause severe damage. Tsunamis result due to earthquakes; gas pipes can burst causing fires; plant and animal habitats including human homes can be destroyed; railroad, highways and bridges can crumble, and the earth s surface can separate and tear apart causing landslides, avalanches, and even floods! Their power should never be underestimated. 1. Based on this passage, do you think Earthquakes are constructive or destructive forces? Provide text evidence. 2. In the first paragraph, what simile is used by the author to compare with the Earth s plates? 3. How are the focus and epicenter alike? How are they different? 4. What are two synonyms the author uses in the third paragraph for the word fault? 5. What is used by scientists to decide the strength of an earthquake? What number would determine a particularly strong earthquake?

Constructive & Destructive Forces Card Sort Activity Using what you know about constructive forces and destructive forces, sort the cards into three piles: constructive, destructive, or both. Use the heading cards to sort.

Constructive Force Destructive Force Both Constructive & Destructive Forces

1. 2. An earthquake breaks apart the land. The rushing Colorado River weathers and erodes rock while creating the Grand Canyon. 3. 4. Cattle graze on grass loosening the soil. An erupting volcano breaks apart the earth s surface, and the lava hardens as it cools forming new land.

5. 6. Acid rain begins to dissolve rock. Glacier pushes the rock slowly over time carving a valley between mountains. 7. 8. A gopher or chipmunk burrows through the ground loosening and moving the soil. A landslide occurs when rock loosens and is pulled down by gravity. Yet, the rock piles up and creates new landforms such as hills.

9. 10. Wind weathers and erodes the rock. Wind deposits sand in dunes across the desert. 11. 12. Water freezes in cracks and breaks the rock apart as the ice expands. The water from a waterfall pounds against the rock weathering it over time.

Head of the Class Instructions Word Association Game for Landforms Cards Timers needed Student draws a card from the deck. Without looking at it, the student places the word card face up on his forehead for partner or group to see. Partner or group gives clues, definitions or examples to get the student holding the card to guess who the character on the card is Student continues to draw cards for the remainder of one minute to see how many he or she can guess. If partner or group can t give a clue, definition, or example they can pass. Those that are passed should be discarded in a separate pile. Keep score by counting all cards guessed correctly in the minute time span. Next student plays from the remaining cards or reshuffles the deck. For example, if the card is weathering, students might say breaking rock rain wind ice mesa, students might say Spanish for table flat top landform igneous rock, students might say not metamorphic porous volcanic deposition, students might say dropping off how a delta forms mouth of the river how sand dunes form

landform mesa sand dune sandbar canyon mountain

volcano weathering hill erosion plain deposition

delta crust magma mantle landslide lava

plates fault earthquake focus epicenter Richter Scale

Barrier Island I am a long, narrow pile of sand that help protect the main land from wave erosion. Rather than being moved by wind, the sand that creates me is moved by the ocean waves and currents. What landform am I? Mountain I am a landform that is much higher than the surrounding land. I like to be with friends arranged in groups called ranges. Some of my kind have tall, jagged peaks while others of us have gentle, rounded slopes. What landform am I?

I am a smaller version of my larger friends mountains. I m just not as high and I tend to have rounded slopes instead of jagged slopes. What landform am I? Hill I am an angry mountain made of lava, ash, or other materials from eruptions. Unlike typical mountains, I like to stand alone instead of in ranges. What landform am I? Volcano

You can think me as a hill made of sand. I was made and shaped by the wind. As the wind blows, it constantly reshapes me. You might find me in deserts or on a trip to the beach. What landform am I? Sand Dune Canyon I am a deep valley with steep sides found mainly throughout the Southwest United States. The grandest and largest of my kind is found in Arizona carved by the Colorado River. What landform am I?

mesa What landform am I? plain What landform am I?