IELTS Reading LEVEL 5.5 – Big News About Old Rocks

Big News About Old Rocks

Grand Old Canyon — Rocks reveal new clues to a complicated history.

Some small rocks from Arizona’s Grand Canyon recently led scientists to a big discovery. The canyon is not just huge, it is also amazingly old. “The traditional view was that the canyon formed 6 million years ago,” said Rebecca Flowers, a scientist at the University of Colorado. Her research, though, shows that the Grand Canyon could be 10 times older.

The canyon is called “grand” because it is so large. It is 277 miles long, up to 18 miles wide, and more than a mile deep. Since ancient times, the canyon has astonished millions of visitors-including plenty of geologists. Geologists are scientists who study Earth’s history by examining rocks, soil, and other parts of the planet.

For decades, geologists thought they knew how and when the canyon formed. Many believed the canyon began to develop 6 million years ago when Earth’scrust, or rocky outer layer, pushed upward. As the crust rose, the Colorado River dug the canyon deeper and deeper through the process of erosion. Erosion is the wearing away of Earth’s surface by water, wind, or ice.

Deep History

Flowers and other scientists used new methods to examine the chemicals in the canyon’s rocks to calculate the age of the rocks. According to their research, parts of the canyon formed at least 55 million years ago. They also found evidence that the Grand Canyon started out as several smaller, separate canyons.

“Different [parts] of the canyon evolved at different times,” Flowers told ScienceSpin. Flowers thinks that the Colorado River probably did cut through Earth’s crust 6 million years ago, but other sections of the canyon formed long before that time. Then the river carved a path between the oldest parts. The smaller gorges joined to become one truly grand canyon.

The new findings fit with other recent research that hints the canyon is older than once thought. Many questions about the Grand Canyon’s history still remain. Scientists are coming up with new ways to study the chemicals in rocks, though, and discovering new answers. Most scientists agree on one thing, says Flowers: “The Grand Canyon does have a complicated history.”

Vocabulary

calculate       cal ·cu ·late

Definition

verb

1. to add, subtract, multiply, or divide in order to find an answer to a number question.

He calculated the cost of a dozen oranges at fifty cents each.

Advanced Definition

transitive verb

1. to compute mathematically.

If you calculate the cost of driving your car to work everyday, you’ll find that it’s much cheaper to ride the bus.

You made an error when you calculated the score.

2. to determine, estimate, or project.

I would calculate that the nearest gas station is about five miles down that road.

The instructor calculated that the students would need two hours to finish the exam.

3. to make suited; design.

It’s a scheme that is calculated to make money.

intransitive verb

1. to determine a result mathematically.
2. to make an assessment or estimation.
3. to depend or count (usu. fol. by upon or on).

I calculated on her being here to help us.

Spanish cognate

calcular: The Spanish word calcular means calculate.

These are some examples of how the word or forms of the word are used:

1. Kepler was the first person to calculate the orbit of Mars.
2. They learn the science of fires, how to calculate water pressure, and how to treat medical emergencies.
3. There are several ways to calculate the risk of a potential hazard becoming real and harming people or property.
4. Flowers and other scientists used new methods to examine the chemicals in the canyon’s rocks to calculate the age of the rocks.
5. Using a spectrometer, astronauts can calculate the temperature of an object in space, learn which direction it’s moving, calculate its speed and weight, and find out what it is made of.

complicate       com ·pli ·cate

Advanced Definition

transitive verb

1. to make (a problem, issue, or situation) more difficult or complex.

We were already lost, but getting the wrong directions only complicated the situation.

adjective

1. involved or intricate.
2. in biology, folded lengthwise several times, as an insect wing or a leaf.

Spanish cognate

complicar: The Spanish word complicar means complicate.

These are some examples of how the word or forms of the word are used:

1. “It’s an amazing job,” he says, “but it’s also challenging. It’s always way morecomplicated than ‘OK, your shoulder hurts, let’s do some exercises.’ You’ve really got to think.”
2. Why is cloning a dog so difficult? Scientists say the reproduction systems of dogs are more complicated than those of sheep, cats, and mice, all of which are easier to clone.
3. Many questions about the Grand Canyon’s history still remain. Scientists are coming up with new ways to study the chemicals in rocks, though, and discovering new answers. Most scientists agree on one thing, says Flowers: “The Grand Canyon does have a complicated“
4. The fame that comes with being a successful actor is more complicated. Being a major movie star, seeing your image 50-feet high on a billboard, is something a lot of children dream about. But it’s not always easy to be a famous actor.

5. As Rodriguez gives his short burst of flame, the air inside swirls in complicated, invisible patterns. Little of it escapes out the hole in the bottom-instead, it cools off gradually by coming into contact with the surrounding air outside the balloon’s thin nylon wall. As this happens, the balloon gradually sinks.
6. The two business partners had to receive various building permits, occupancy permits, and build their tents according to state and fire codes. It was a complicated process, and each time they thought they were forging ahead, an inspector paid a visit to their site and told them about yet another rule that they had to abide by.
7. Freamon had drawn a complicated diagram of all the creatures living in the nearby Ho Tep Wildlife Reserve. Every type of living thing, from trees and insects to mammals and birds, was written down and circled on the board. Arrows snaked around the board, connecting the circles, showing which creatures depended on which other creatures to survive.
8. To reuse material is to find a new place and use for material no one uses anymore. These other places could be old houses being torn down, construction sites and recycling centers like junkyards and scrap yards. It can be as simple as buying a used bathtub and putting it in the new house. Or it can be more complicated, like using the metal from old umbrellas to make lighting fixtures.

examine       ex ·am ·ine

Definition

verb

1. to look at in a close, thorough way.

The doctor examined my eyes and ears.

Advanced Definition

transitive verb

1. to inspect or evaluate thoroughly.

The archaeologist examined the coins that were found on the site.

The detective examined the fingerprints.

2. to test by asking questions or posing problems for solution.

The committee examined each candidate before making a decision.

The students will be examined on all aspects of the material covered in the course.

3. to inspect (a body or body part), esp. in order to ascertain general health or cause of illness.

The doctor examined my sore foot.

4. in law, to formally interrogate.

Do you wish to examine this witness?

Spanish cognate

examinar: The Spanish word examinar means examine.

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