INTRO Flashcards
1
Q
what is oceanography?
A
act of recording and measuring the oceans
2
Q
how thick is earth crust?
A
30 - 50 km
3
Q
how thick is the mantle?
A
2900 km
4
Q
how thick is the core?
A
3500 km
5
Q
characteristics of shelf?
A
- nearly flat
- 1 - 1000km wide
- 0.5° slope
6
Q
characteristics of shelf break?
A
- 130 m depth
- 1 - 4°
7
Q
characteristics of slope?
A
- 4° slope
- 2- 3 km depth
- submarine canyons
8
Q
characteristics of rise?
A
- 1° slope to 500 km offshore
- 4 km depth
9
Q
characteristics of deep sea trench?
A
- long narrow depressions
- 3 - 5 km deep
- seismic
10
Q
characteristics of abyssal plains
A
- 3- 5 km depth
- land derived sediment
100 - 1000 km thick
11
Q
characteristics of abyssal hills?
A
- < 1000m high
- 100 - 1000km wide
- volcanic rocks
12
Q
characteristics of seamounts?
A
- extinct/ active volcanoes
- > 1000m high, guyots
13
Q
characteristics of continents?
A
- 29% of surface
- mean height = 0.84 km
- granitic rocks
- igneous
- 2700kg/m^3
- 30 - 40 km thick
14
Q
characteristics of ocean basins
A
- 71% of surface
- mean depth = 3.8km
- basaltic rocks
- 2900 kg/m^3
- 4- 10 km thick
