Oceans and Marine Geography Concepts

Oceans cover 71% of Earth's surface and contain 96% of its water. The Pacific Ocean is the largest, while the Arctic is the smallest. Oceans play a crucial role in regulating Earth's climate and are home to many undiscovered species. Despite their vastness, only 5% of the ocean has been explored. Seas are smaller areas of oceans, and the mid-ocean ridge is the longest mountain range on Earth, located underwater. There are 1,500 active volcanoes on Earth's surface, but the Pacific Ocean alone may contain over 10,000 volcanoes.

What percentage of the Earth's surface is covered by oceans?

• 50%

• 71%

• 85%

• 96%

Which ocean is the largest in the world?

• Arctic Ocean

• Pacific Ocean

• Indian Ocean

• Atlantic Ocean

What percentage of the ocean has been explored by humans?

• 20%

• 10%

• 50%

• 5%

What is a sea in relation to an ocean?

• A deep part of the ocean

• A type of ocean current

• A small area of ocean

• A large ocean

What is the name of the longest mountain range on Earth found underwater?

• Andes

• Himalayas

• Mid-ocean ridge

• Rocky Mountains