Continents and Oceans: The Building Blocks of Earth’s Geography

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A continent is a large continuous mass of land.  A large subdivision of a continent is known as a subcontinent. The seven continents are North America, South America, Europe, Asia, Africa, Australia, and Antarctica. Sometimes, Oceania is counted as an eighth continent. An ocean is a large body of salt water. The world is one big ocean divided into five oceans to help us organize things: the Atlantic, Pacific, Indian, Artic, and Southern (the newest).  

The Whole Wide World  

History is the study of past events. World history involves the study of the events of the whole world.  The world is a big place.  We can make it easier for ourselves by breaking things down. 

Geography is the study of places and our relationship with them.  Geography is quite important.  Continents and oceans are fundamental aspects of world geography.  


What Is A Continent? 

A continent is a large continuous mass of land.  

Continents are usually separated by large bodies of water.  

A subcontinent, such as India, is a large segment of a continent.  Islands and water around a continent are part of the continent itself.  

How Did The Continents Form? 

The earth formed from a cloud of dust and gas billions of years ago. The earth cooled and the result was three layers: a core at the center, a middle (mantle), and an outer layer (the crust).   

The crust and the top portion of the mantle form a rigid shell around the earth that is broken up into huge sections called tectonic plates.  

The earth’s crust moved around over the years.  Over two hundred million years ago, there was one big “supercontinent” known as Pangaea (“all lands”). This supercontinent (did it have superpowers?) then broke apart into the continents we know today.

Seven (or Eight) Continents  

The world today is broken up into seven continents: North America, South America, Europe, Africa, Asia, Australia, and Antarctica. Sometimes, Oceania is added. 

We divide the earth into four parts, known as hemispheres, that match the points of the compass. So, we have the Northern, Southern, Eastern, and Western Hemispheres.   

Europe and Asia sometimes are labeled as one continent (Eurasia).  The islands of the Pacific are sometimes classified as a separate continent called Oceania.  At times, Australia is deemed part of Oceania.  Sounds interesting? Learn more about continental boundaries.   

What Continent Is The United States In?

Continents are broken down into many separate political communities.  Australia is the only continent that is its own country.  Antarctica is the only one that has no countries.  

The United States is mostly in North America.  The “continental United States” is another name for the forty-eight states found between the Atlanta and Pacific Oceans.  Alaska is separate but still in North America.  Hawaii is part of Oceania.   

U.S. territories also are found outside of North America, including Guam.  


What Is An Ocean?  

An ocean is a large body of salt water.  They are a type of basin, a depression on the earth’s surface that often are filled with water.  Over 70% of the world is made up of oceans. 

The Earth is special.  Its location in our solar system allows water to exist in all its phases, gas (water vapor), liquid (water), and solid (ice).  It is the only planet in our solar system like this.

The presence of large amounts of water sustains life on Earth.  

What Are The Five Oceans? 

The world is one large ocean.  Geographers, however, divide it into five separate oceans. These oceans are the Atlantic, Pacific, Indian, Artic, and Southern (Antarctic) Oceans. The Southern Ocean is the most recent to be labeled a separate ocean.

The Atlantic Ocean separates the Americas from Europe and Africa.  The Pacific Ocean is the largest.  It separates the Americas from Asia and Australia.  

The Arctic Ocean is the smallest and surrounds the North Pole. The Southern Ocean is the second smallest and surrounds the South Pole.  

The Indian Ocean separates Africa from Australia. It is the warmest ocean in the world.

Some Other Ocean Related Terms 

A sea is often used as another word for “ocean” such as “going out to sea.”  

A sea is geographically used to mean a smaller body of water where oceans and land meet. 

The “seven seas” are the Indian Ocean, Black Sea, Caspian Sea, Adriatic Sea, Persian Gulf, Mediterranean Sea, and Red Sea.

A bay and gulf are places where land meets water.  A bay (San Francisco Bay) is part of the coast surrounded by land on three sides. A gulf (the Persian Gulf) only provides one narrow opening.  Bays and gulfs are important for fishing and shipping. 

A strait (Strait of Gibraltar) is a narrow passage of water.  

Why Is the Ocean So Salty? 

Humans need fresh water to survive.  So, it’s a bit complicated that nearly all of the Earth’s water is salty (saline).  On the other hand, lots of animal and plant life thrive there.

Where did all that salt come from?  Rain hits the land and erodes (breaks down) the rocks.  Water carries the salts and minerals into the oceans.  Some salt also comes from cracks in the ocean floor.  Salt seeps up into the ocean.  

Columbus Sailed the Ocean Blue … 

A lot of human history involved humans crossing over continents and oceans.  

Inuits look Asian because they traveled from Asia a long time ago. Moana went on an adventure to lead the way for her people to explore Oceania.  

The location of Spain and Portugal greatly influenced their role in the European colonialization of the Americans.  And, years later, the United States fought in the Spanish-American War partially to have Pacific bases that were important for worldwide commerce. 

Geography, including continents and oceans, continue to be an important means to understand the world and its history.

Teach and Thrive

A Bronx, NY veteran high school social studies teacher who has learned most of what she has learned through trial and error and error and error.... and wants to save others that pain.