6th Performance Task #3

Source #1 

This article from Appleseeds magazine is about the formation of the Grand Canyon. 

The Three “R”s of Folding Time Grand Canyon Style 

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by Leigh Anderson 

There is a place—like no other in the world—where time seems to fold in on itself. Where the past meets the here-and-now, mountains meet oceans, beauty meets danger, and discovery meets mystery. This place is the Grand Canyon. 

The Grand Canyon is 277 river miles long. At certain points, it’s more than a mile deep and as much as 18 miles wide. Going 50 miles per hour, it would take over five hours to drive its entire length! At such speed, you’d hardly see any of what makes the canyon truly grand: dazzling, glittering colors; fossils and wildlife; a great river snaking through . . . rock; and many layered canyon walls giving glimpses of Earth’s history. 

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Geologists, people who study rocks, minerals, and soils of the earth or a particular area, have many, different . . . [ideas] about how and when the Grand Canyon was formed. The story of the canyon’s beginnings is like a jigsaw puzzle with many pieces missing. There are a few things geologists do agree on. We’ll call them the three “R”s: Rocks, River, and ‘Rosion (actually, Erosion, a process by which rock, soil, or sand is gradually worn away by water, wind, or ice, but we’re going to cheat a bit!).

Rocks

The Grand Canyon’s walls are made up mainly of three types of rock: limestone, sandstone, and shale. Over . . . [thousands of] years, the rock built up layer by layer. Each new layer of rock pressed down on the layers beneath it. Then the Colorado River began to cut through these layers like a knife, exposing them for us to see. At the Grand Canyon today, 18 or more layers of Earth’s history are laid out for us to see. We can see backward in time! The rocks near the top of the canyon are . . . [very] old, but those toward the bottom of the canyon are . . . [thought to be over six times older]. What an amazing place for scientists to study the history of Earth.

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Limestone, sandstone, and shale: Each of these types of rock was formed in a different way. Limestone is made from the fossilized skeletons of tiny organisms that lived in ancient seas. (Fossils are the super hard remains of plants or animals . . .) Sandstone is actually sand, pressed so hard over . . . [thousands of] years that it stuck together into rock. And shale is basically mud, left over from the bottoms of ancient lakes and marshes. Some rock is softer, some is harder, and they erode at different rates. When a layer of hard rock is on top of a layer of softer rock, amazing cliffs are created. . . . 

River

Without the Colorado River, there would be no Grand Canyon. The river flows southwest from the Rocky Mountains to the Gulf of California, crossing through an area called the Colorado Plateau. As it flows, the river crosses Colorado, Utah, Arizona, and Nevada before flowing into Mexico and the Gulf. But the ancient Colorado was not the same river we know today. In fact, long ago it was probably more than one river. When those ancient rivers joined, the newly formed Colorado began flowing southwest. It bucked over dangerous rapids and frothed like chocolate milk in a blender as it carried mountains of dirt downstream. Like sandpaper repeatedly rubbing the same piece of wood, the fast-moving, sand-filled water slowly carved a groove in the rock beneath it.

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But the Colorado River didn’t carve the canyon by itself. As ancient glaciers melted, the river and its tributaries, smaller rivers and streams that flow into a larger river, flooded again and again. The floods cleared away the sand, gravel, and other sediment at the bottom of the river. Then, rocks and boulders, which had tumbled into the river, were able to grind and scrape the bedrock at the river’s bottom, further deepening the canyon.

As water moves through the canyon, it flows “downhill,” dropping in elevation. This makes the water flow faster, with more power to carve out the rock. Also, long ago, the land around the Colorado River began to rise bit by bit, bubbling upward like a giant blister. Known as uplift, this process continued over . . . [many] years. Uplift helped form the canyon we know today.

What Do You Think? The Colorado River Today 

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Today, the Glen Canyon and Hoover Dams tightly control the Colorado River. The river now runs more slowly. Floods no longer sweep away the sediment at the bottom of the river. The river-bottom sediment is 75 feet deep in some places! Because of the slower water and the thick “blanket” of sediment, the carving of the canyon has slowed down. . . .

‘Rosion

When rain falls on rocks, water seeps into the cracks in the rock. When the weather gets cold and that water freezes, it expands, or gets bigger. Over and over, water freezes and expands in the cracks. And slowly, the rock splits apart. Pieces of broken rock (from tiny to huge) fall into the canyon below. As they fall, they might hit another rock and send it tumbling too. When they finally reach bottom, some rocks are carried away by the Colorado. Others remain where they landed.

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Heavy rains send great slabs of sediment, mud, and rock crashing down cliff faces, widening the canyon and carving new shapes into the giant red walls. The Colorado’s tributaries are busy, too, carving smaller side canyons. Sometimes these side canyons erode into each other, further widening the canyon. This is all part of the process of rocks, river, and ‘rosion that makes this canyon so GRAND!

Source #2 

This article from Appleseeds magazine is about how to take a nature walk. The article talks about John Muir, a man who loved nature and encouraged leaders to preserve land in the United States so people could enjoy its natural beauty for many years. The article explains what John Muir did on a nature hike. One place that he loved to explore was the land that is now known as Yosemite National Park.

Follow in Muir’s Footsteps—Take a Nature Walk 

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by Michelle Schaub

“In every walk with nature, one receives far more than he seeks.” —John Muir

From the steamy swamps of Florida to the icy glaciers of Alaska, John Muir loved exploring wild places. Wherever he went, he carried a notebook to describe the wonders he discovered. You don’t have to walk a thousand miles to follow in Muir’s footsteps. You can connect with nature by taking a simple walk and recording your observations in a journal.

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Just follow these steps: 

1. Pick a “wild” place—A nature trail, arboretum (a place where you can see special trees), park, or even your own backyard. 

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2. Bring a notebook—Large enough to fit your writings and drawings but small enough to carry comfortably. 

3. Pack a snack—While John Muir brought only tea and bread on some of his journeys, you might want to pack a tastier treat. Just remember not to litter. 

4. Be alert—Let the sights, sounds, smells, and textures of nature fill your senses. 

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5. Look high and low—Notice the big picture, like landscapes and trees, but also the little details, like flower petals and insect wings. 

6. Write it down—Use plenty of descriptions to record your observations. Add your thoughts, feelings, and questions. Don’t forget to put the date, time, and location on each entry. 

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7. Add drawings—Muir filled his journals with sketches of the plants and animals he encountered. Sketching will help you focus on details you might otherwise miss. 

8. Collect plants—Try pressing flowers and leaves between the pages of your journal, just like Muir did! 

9. Take pictures—If you can’t collect plants where you are hiking, take pictures and tape them into your journal instead. 

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10. Learn more—Did you observe something on your walk that sparked your interest? A bird’s feather? A strange fungus? Use the descriptions and drawings in your journal to look up more information.

Next time you take a walk in a wild place, you’ll be a keen nature observer! 

Source #3 

This article from Appleseeds magazine is about hiking in the Grand Canyon. 

Take a Hike! 

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by Kathiann M. Kowalski

Each year, more than 250 hikers need assistance at the Grand Canyon. If  you plan ahead and use safety smarts, you can avoid becoming number  251! And you can have a great hiking adventure. 

The Lay of the Land 

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■ Know what to expect. The Grand Canyon is like “an upside-down  mountain,” notes National Park Service Ranger Marc Yeston. Hiking down is  much easier than climbing out. The park’s website suggests allowing twice  as long to climb up as it took to go down. 

■ Be realistic about your abilities. Start with short hikes. DON’T try hiking all  the way down the Grand Canyon and back in one day. 

■ Get trail maps and read rules. Day hikes in the canyon require no permits,  but overnight hikes do. Some trails have bathrooms and water during parts  of the year. 

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■ Kids: Always hike with an adult. 

■ Tell friends or family members about your plans. 

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“Know what the weather is going to be like,” says Ranger Yeston. Then  prepare for the worst. Carry extra clothes and flashlights in case it’s dark  when you return. 

“People hike every day of the year,” notes Ranger Yeston, but each season  brings special risks. Ice is a danger in winter. In the summer, temperatures  at the bottom of the canyon can soar to 115° F! When it’s hot, smart hikers travel before dawn or after sunset during the cooler times of day. Spring and  fall have warm, pleasant days, but nights get frigid. And storms can crop up  any time, in any season. 

On the Trail—Do’s and Don’ts 

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■ Don’t hike alone. 

■ Do use common sense and safety smarts. Avoid the trail  edges. 

■ Do carry plenty of food, water, and salty snacks. They provide energy and  replace water and salts lost through sweat. Enough water can make the  difference between an enjoyable experience and a dangerous situation.

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■ Do rest often in the shade.

■ Do wear good, comfortable hiking shoes and socks. 

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■ Do carry hiking poles if you can, especially in steep spots.

■ Do watch out for wild animals. If you are lucky enough to encounter one, don’t feed or try to touch it. 

■ Do remember that mules use hiking trails too. To avoid accidents, wait  quietly on the inner side of the trail until they pass. 

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■ Don’t litter. Do respect the environment and carry out all trash. Then  everyone can enjoy nature’s beauty! 

Source #4 

This article from Appleseeds magazine is about preserving the Grand  Canyon.  

How to Be a Green Traveler 

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by Katherine Swarts 

Every year, between four and five million tourists visit Grand Canyon  National Park. Even with 1.2 million acres to explore, all those people strain  the park’s ecosystem, a group of plants and animals and the environment they live in. Many overlooks and trails have been badly eroded by  millions of feet. Winds bring smog from cities. Planes cause noise pollution.  Dams on the Colorado River slow the flow of the water, causing many  unnatural changes. 

When you visit the Grand Canyon, you won’t be able to solve these  problems. But there are a lot of things you can do to be sure you don’t make  them worse. 

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■ Never feed or try to touch wild animals, no matter how cute they might be.  Human food is not good for wild animals, and too much of it can make  animals dependent on people. 

■ Never pick plants or collect rocks. Many are rare or delicate. It’s also  against the law! 

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■ Ask your parents to leave the car in Williams, Arizona. From there, you can  take the Grand Canyon Railway to the South Rim. 

■ Stay on well-traveled trails. Never take shortcuts—they damage the land by contributing to erosion. And some rare plants can take a hundred years  to recover from being stepped on! Shortcuts can also lead you into  dangerous places. 

■ Use recycling bins and litter cans. At the North Rim and other areas with  few bins, take along bags to carry your trash out. Never toss anything on  the ground, not even an apple core. 

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■ If you’re lucky enough to encounter a California condor—one of the biggest  and rarest birds on Earth—stay at least a hundred yards away. And tell park  rangers about any condors you see. That helps scientists keep track of the  birds.  

■ Don’t use more water than you need. This is your chance to go without a  bath! (Remember to drink lots of water though.) 

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■ Don’t drive anywhere you can walk—or take the free shuttle buses. • If you want to do something big for the park, ask visitor services about the  Junior Ranger Program or Habitat Restoration Program. 

■ If you see other visitors doing things that hurt the park, speak up in a  friendly way. Remind them that it takes everyone’s efforts to keep the Grand  Canyon beautiful.