Why is the Dead Sea called the Dead Sea?

Table of Contents

Sitting between the countries of Jordan and Israel is a body of water called the Dead Sea. It is the lowest point on land, its surface being 1,400 ft (430 m) below sea level, while its deepest point is another 1,000 feet below. Hearing this name may make you think it is an ocean. However, this unique body of water is a salt lake . Other salt lakes you may be familiar with include the Great Salt Lake in Utah and the Caspian Sea.

 

Discover the fascinating geology and ecology and uncover the reasons why this body of water has such a curious name.

Dead sea
Dead Sea, Credit: Wikimedia/David Shankbone

What is a salt lake, and how does it form?

From the name ‘salt lake,’ it is clear that these lakes are saltier than a normal lake. Surprisingly, salt lakes can be even saltier than the ocean! They even contain different types of salt, including sodium chloride , or table salt.

 

Salt lakes can form in different ways. The Dead Sea is specifically formed because of large plates shifting under the Earth’s surface. Over a million years ago, the African Plate and the Arabian Plate shifted, causing a ditch to form. This ditch was originally connected to the Mediterranean Sea, so it was full of water. Over time, the plates shifted again, cutting the Dead Sea off from the Mediterranean Sea. The Arabian Plate is moving faster, increasing the separation. This is why it now exists as a lake on its own.

 

However, the Dead Sea was a different lake in the Pleistocene era, almost 55,000 years ago. It was called the Lisan Lake. Interestingly, at that time it was three times the size of the modern Dead Sea. In fact, sediments left by this lake are still found in Jordan Valley. Moreover, a salty peninsula called the Lisan Peninsula still divides the Dead Sea.

 

How did this lake become so salty? After it was separated from the Mediterranean Sea, the water levels retreated, leaving behind much saltier water. In addition, the only remaining source of water is the Jordan River which sends both water and sediment into this lake. After the sediment settles, the salt content of the lake increases even more. There is nowhere for the water to go once it has reached the Dead Sea’s dead end.

 

When rocks from deep beneath the earth intrude into brittle rocks on the surface, structures called diapirs form. There are two diapirs that have formed in the area: the Sedom diapir and the Lisan diapir. As these are salt diapirs, they also add to the salinity of the Dead Sea.

How did the Dead Sea get its name?

Now that we know how it got its saltiness, how did this body of water get its name? Salty water is not always good for animals and plants. We know that many animals and plants survive in the ocean happily. However, the lake is nine times saltier than the ocean! That amount of salt prevents animals and plants from being able to survive. So the reason it was named the Dead Sea is for its lack of living organisms.

Does anything live in the Dead Sea?

Although animals and plants cannot survive in the super salty lake, there are some microorganisms such as bacteria and fungi that live here. Specific types of bacteria and fungi can survive different types of living conditions that more complicated organisms cannot survive.

 

In the past, when rain poured into the lake, the level of saltiness changed, and so did the microorganisms that lived there. With a lower salt content, new microorganisms were able to tolerate and thrive here, including brilliant red Dunaliella algae. However, when the water returned to its saltier state, these algae could no longer survive.

 

So only the bacteria and fungi that can survive the saltiest conditions survive here. The algae stay dormant most of the time. They bloom only after rainfall because the saltiness is lowered. They have a large and peaceful home – until people come to explore.

A salt lake containing Dunaliella algae
A salt lake containing Dunaliella algae, Credit: Wikimedia/Adolf Engler, K. Prantl

Can people swim in the Dead Sea?

Even though animals and plants cannot live in the Dead Sea, it is possible for humans to get into the water. People can try to swim in it, but they may have a bit of trouble. With the high salt content, the easiest thing to do in this water is to simply float. This is because the saltiness of the water forces the body to float to the surface. Therefore, it is just impossible to sink. And even if you attempt to kick your feet and swim, you will find your feet being forced upwards. So the best thing to do here is to sit back and relax!

A person floats in the Dead Sea
A person floats in the Dead Sea, Credit: Wikimedia/TijsB

Science Experiment: Make a Dead Sea in a cup

It’s time to “Sea” what the Dead Sea is like!

 

1. Find a glass or any cup that you can see through.

 

2. Fill the glass with water.

Glass of water
Get a glass of water

3. Get an egg. Place the egg gently into the water. You’ll see it fall to the bottom of the glass.

bottom of water
Put an egg in the water

Note: Some eggs will float in the water. This means the egg is a little older. If you can find a fresher egg, use that one instead.

 

4. Start adding salt to the water slowly. Add it little by little, stirring the water as you go.

 

5. As you add more salt, watch the egg float to the top of the water!

Floats
Add salt and mix. Continue adding salt until the egg floats

Science behind the Dead Sea

Adding salt to water can change the density  of water, making it heavier than normal water. During the experiment, the salt water becomes heavier and heavier until its density is higher than the density of the egg. This causes the egg to float all the way to the top of the water, much like you would float in the Dead Sea!

Another type of lake : Soda Lakes

Freshwater lakes, salt lakes, and soda lakes… Oh my! Have you cooked with baking soda? Baking soda gets its name from its composition, which is sodium bicarbonate. Soda lakes are similar to salt lakes, but they have a higher amount of carbonates , like those found in baking soda. 

 

Popular Soda Lakes  

1. Soap Lake in Washington

2. Lake Shala in Ethiopia

3. Lake Zabuye in Tibet

Glossary

Salt Lake – a lake with a high amount of salt

 

Sodium Chloride – table salt, also found in salt lakes

 

Plates – pieces of the Earth’s crust that move below the surface of the Earth

 

Sediment – particles that settle at the bottom of the water

 

Microorganism – tiny organisms like bacteria or fungi

 

Density – a measurement of how much mass is in a space

 

Carbonate – a type of salt

Flesch Kincaid Score: 75.3

 

Flesh-Kincaid Grade Level: 6

Contributors

  • Tess Bub
    : Author
    Tess Taggart Bub has a bachelor’s degree in biochemistry and a minor in data science from Houghton College. During her undergraduate studies, she conducted research in the areas of climate science, ecology, and muscle biology. She is currently a PhD candidate at the University of Tennessee Health Science Center studying host cellular response to viral infection. She is a strong believer that science can change the world, especially when it’s shared. In her free time, she loves communicating science, playing guitar and piano, and running. Writing for smore gives Tess the opportunity to help inspire a new generation of women in STEM.

Copyright @smorescience. All rights reserved. Do not copy, cite, publish, or distribute this content without permission.


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