The salty water that covers a large part of the surface of the earth, or a large area of salty water, smaller than an ocean, that is partly or completely surrounded by land
A sea
15
A mountain with a large, circular hole at the top through which lava (= hot liquid rock) gases, steam, and dust are or have been forced
Volcano
15
A row of mountains
a mountain range
15
An area of a country that is protected by the government because of its natural beauty or because it has a special history
a National Park
15
A hill of sand near a beach or in a desert.
Dune
15
The shape of a bone, a shell, or a plant or animal that has been preserved in rock for a very long period
Fossil
15
An area, often covered with sand or rocks, where there is very little rain and not many plants
Desert
15
A sudden violent movement of the earth's surface, sometimes causing great damage