What's My Shape?

Take two minutes to think about landforms!

1. List two different landforms you already know.
   
   
   
2. Write down one question you have about how landforms are made or what they look like.
   
   
   
   

Earth's Marvelous and Moving Landscapes

The Earth's surface is a dynamic canvas, constantly being shaped by powerful natural forces. While we often think of towering mountains and vast plains, there are many other incredible landforms that tell stories of water, wind, and ice.

River Deltas: Nature's Spread-Out Snacks

Imagine a busy river, carrying tons of mud, sand, and tiny rocks all the way from the mountains. When this river finally reaches a large, still body of water, like an ocean or a big lake, it's like a person dropping a heavy backpack after a long hike. The river slows down, and all that sediment it was carrying settles to the bottom.

Over many years, this deposited material builds up, forming new land. This new land often fans out in a triangular shape, much like the Greek letter delta (Δ). These river deltas are incredibly fertile areas, rich in nutrients, making them important habitats for wildlife and valuable farmland for humans. The Ganges-Brahmaputra Delta in Bangladesh and India is one of the largest and most famous examples in the world.

Sand Dunes: The Wind's Sculptures

Not all landforms are shaped by water! In deserts and along some coastlines, the wind takes center stage. Strong winds pick up loose sand particles and carry them. When the wind hits an obstacle, or slows down in a sheltered area, it drops the sand, and these piles begin to grow. These hills of sand are called sand dunes.

Sand dunes aren't stationary; they are constantly shifting and moving with the wind, sometimes slowly marching across a landscape. Their shapes can vary greatly, from crescent-shaped barchan dunes to long, parallel linear dunes. The Thar Desert in India is home to many magnificent sand dunes, constantly being reshaped by the desert winds.

Glaciers: The Slow but Mighty Ice Movers

Think of a river, but instead of water, it's made entirely of ice! Glaciers are massive bodies of ice that form over many, many years in areas where more snow falls in winter than melts in summer. As layers of snow pile up, the weight compresses the lower layers into dense, solid ice.

Once thick enough, glaciers begin to flow slowly under their own immense weight, like a very thick, slow-moving liquid. As they creep across the land, they pick up rocks and sediment, grinding away at the landscape. Glaciers are incredibly powerful erosional forces, carving out deep valleys, creating sharp mountain peaks, and forming lakes. The Himalayas, for instance, are home to numerous glaciers that feed many of India's major rivers.

Waterfalls: Nature's Leaping Waters

Everyone loves a good waterfall! A waterfall is a place where river water flows over a vertical drop or a series of steep drops in its course. They usually form when a river flows over different layers of rock that erode at different rates.

Imagine a river flowing over a layer of hard rock sitting on top of a softer rock layer. The softer rock below gets eroded away more quickly by the flowing water, undercutting the harder rock above. Eventually, the harder rock overhang collapses, and the waterfall recedes upstream. This continuous process creates the stunning cascades we see around the world, like the famous Jog Falls in Karnataka, India.

Landform Fact Hunt!

Instructions: Read the "Unusual Landforms Reading" and use the information to answer the questions below about Deltas, Sand Dunes, Glaciers, and Waterfalls.

River Deltas

1. What is a river delta?
   
   
   
2. How does a river delta form? What does the river deposit?
   
   
   
   
3. Why are deltas considered important areas?
   
   
   

Sand Dunes

1. What forces create sand dunes?
   
   
   
2. Describe how sand dunes are formed.
   
   
   
   
3. Do sand dunes stay in one place? Explain.
   
   
   

Glaciers

1. What is a glacier?
   
   
   
2. How do glaciers form over time?
   
   
   
   
3. Name two ways glaciers impact or change the landscape.
   
   
   

Waterfalls

1. What is a waterfall?
   
   
   
2. How do different rock layers contribute to the formation of a waterfall?
   
   
   
   
3. What happens to a waterfall over a very long period of time, according to the reading?
   
   
   

Landform Bingo!

Instructions: Your teacher will call out descriptions or characteristics of landforms. If you have the landform on your bingo card, mark it off! The first person to get 5 in a row (horizontally, vertically, or diagonally) shouts "BINGO!"

Bingo Card (Example)

• Definition: Landform created when a river deposits sediment as it enters a body of water.

  • Answer: Delta

• Definition: Hills of sand formed by the wind, often found in deserts.

  • Answer: Sand Dune

• Definition: A large, slow-moving mass of ice that carves landscapes.

  • Answer: Glacier

• Definition: A place where river water drops abruptly from a height.

  • Answer: Waterfall

• Definition: The process of wearing away land by wind, water, or ice.

  • Answer: Erosion

• Definition: Material like sand, silt, and mud carried and deposited by water or wind.

  • Answer: Sediment

• Definition: A long, narrow depression in the Earth's surface, typically formed by water or glaciers.

  • Answer: Valley

• Definition: A natural flowing watercourse, usually freshwater, flowing towards an ocean, sea, lake or another river.

  • Answer: River

• Definition: Often triangular in shape, found at the mouth of a river.

  • Answer: Delta

• Definition: Can 'sing' or hum as wind blows over them.

  • Answer: Sand Dune

• Definition: Responsible for shaping many U-shaped valleys.

  • Answer: Glacier

• Definition: Formed when a river flows over hard rock layers on top of softer ones.

  • Answer: Waterfall