1. Mid-Ocean Ridges
JdFR
MAR
CIR
EPR
SWIR
PAR
SEIR
Thuan Chau, Yao Yao

2. Mid-Ocean Ridge Underwater mountain system formed by plate tectonics.
Oceanic spreading center
Valley of rifts running along its spine
Responsible for seafloor spreading
Magma, which comes out at the linear weakness part in the oceanic crust, becomes the new seafloor when it cools down.
Longest mountain range in the world 80,000km long (65,000km continuous).

3. Classes of Ridges
Fast-spreading ridges, like the East Pacific Rise, the spreading rate is 100 to 200 millimeters per year.
Slow-spreading ridges, like the Mid Atlantic Ridge, the spreading rate is 20 to 40 millimeters per year.
Ultraslow-spreading ridges, like the Southwest Indian Ridge, the spreading rate is less than 20 millimeters per year.

4. Central Indian Ridge:
Western regions of the Indian Ocean.
Lava flow: km3/year
Average spreading rate: 1.13 cm/year
Southwest Indian Ridge:
Southwest Indian ocean
Separated the African and Antarctic plates
Average spreading rate: mm/year
Mid-Atlantic Ridge:
Atlantic Ocean
Separated Africa and South America
Average spreading rate: 2.5 cm/year

5. Southeast Indian Ridge: Intermediate spreading ridge ~60 to 80 mm/yr
Juan de Fuca Ridge:
(500km long, 8km wide)
Subduction zone, divergent zone, transform zone.
1.8 to 3 cm/yr.
frequency of seismic events.
East Pacific Rise:
Volcanic chain – 1,800 to 2,700 m above seafloor
16 cm/ yr (Chile)
6cm/yr (Gulf of California)
Pacific Antarctic Ridge:
Divergent tectonic plate boundary located in the South Pacific Ocean.
Rate of spreading is 54-76mm/yr.
Southeast Indian Ridge:
Intermediate spreading ridge
~60 to 80 mm/yr