Across
1
Ocean between Americas and Europe/Africa
6
Ridge of rock or coral near the surface
7
Largest river in South America
8
Wearing away of land by water or wind
9
Chain or group of islands
10
Flat elevated area of land
11
Dry land with little rainfall
13
Height above sea level
Down
2
Half of the Earth
3
Land surrounded by water on three sides
4
One of seven major landmasses
5
Cold treeless Arctic plain
12
Region between the two tropic lines