Across
1
Low-lying land surrounded by higher ground
4
Wearing away of land by water or wind
5
Land surrounded by water on three sides
6
Piece of land jutting into the sea
9
Largest ocean on Earth
12
Half of the Earth
Down
2
Flat elevated area of land
3
Largest river in South America
7
Large body of water partly enclosed by land
8
One of seven major landmasses
10
Ridge of rock or coral near the surface
11
Large slow-moving mass of ice
13
Cold treeless Arctic plain