Across
1
Mountain that can erupt with lava
4
Seasonal heavy rainfall
5
Deep narrow valley with steep sides
6
Half of the Earth
7
Low-lying land surrounded by higher ground
8
Largest river in South America
11
Narrow sea inlet between cliffs
Down
2
Line dividing two countries
3
Total number of people in an area
4
Large natural elevation of earth
9
Ridge of rock or coral near the surface
10
Imaginary line around the middle of Earth
12
Region surrounding the North Pole