The Mid Ocean Ridge is an underwater mountain range that is formed by the plate tectonics. The mid ocean ridge is the longest mountain range on Earth. One of the proof is that its peaks are even higher than the Alpine’s peaks. The size of the mid ocean ridge is about 35,000 miles long or 60,000 km and it covers over 23 percent of the Earth’s surface. The total length of the ridge is as much as circling around the world to times. Mid ocean ridge goes through the middle of Atlantic ocean, to the Indian and Pacific ocean.
See also: Types of Ocean Rays
There are two types of mid ocean ridges:
- Fast-Spreading Ridges
The northern and southern East Pacific are one of the fast-spreading ridges. They have smoother topography at the crest of their ridge and look similar to domes. They have relief of about 328 up to 656 feet or equal to 100 to 200 meters. The East Pacific Rise itself can move about 15 centimeters every year or equal to 5.9 inches.
The fast-spreading ridges are somewhat “hotter” than the slow-spreading ridges, making them have more magma beneath their ridge axis and more volcanic eruptions to occur than those slow-spreading ones.
See also: Types of Ocean Vegetation
- Slow-Spreading Ridges
One of the slow-spreading ridges is the Mid-Atlantic Ridge whose wide, large, rift valleys can sometimes be as wide as 6 to 12 miles or equal to 10-20 kilometers. Their terrain is very rugged at the ridge crest and can relief up to 2 miles or 3.2 kilometers. The Mid-Atlantic Ridge itself moves only on the average of 1 inch or 2.5 centimeters every year.
See also: Types of Ocean Crabs
Here are some of the famous mid-ocean ridges:
- Mid-Atlantic Ridge, Atlantic Ocean
- Southwest Indian Ridge, Atlantic and Indian Oceans
- Explorer Ridge, Pacific Ocean
- East Pacific Rise, Pacific Ocean
- Pacific-Antarctic Ridge, Pacific Ocean
See also: Types of Ocean Shrimp
Now, after learning the types of mid-ocean ridges and some of the famous ridges, let’s start to learn what is actually the importance of mid ocean ridges.
- Iron Source
One of the importance of mid ocean ridges is that they are estimated to produce iron that makes up about 25 to 75 percent of global ocean iron stocks. It also appears that the iron produced by the mid ocean ridge have a much longer lifetime and can be exported from the ridge until up to 4,000 km away from its initial place.
See also: Types of Ocean Parasites
- Mix Iron to Surface Waters
The mid oceanic ridge is also believed to be able to mix the iron derived from it with the surface waters. This mix is important since it is needed to drive biological activity. It also appears that the interaction itself by the ridge and deep ocean tide can is capable to elevate the rate of physical mixing.
If the mid ocean ridges are proved to increase the vertical mixing, it can be implication to know that the regions may exhibit an efficient transfer or iron to the surface waters. This phenomenon can be a main key to supply a large-scale of iron to the surface waters.
See also: Ocean Plants
- Support Ocean Life Forms
Around the hydrothermal vents that occur along the ridge axes, we can find an abundant amount of chemosynthetically-supported life. The vent fields also contributed, although only for small amount, to the mid ocean biological productivity.
The mid ocean ridge system also has a secondary biological productivity whose source is from the downward export of organic carbon of photosynthesis in the surface layers of the ocean.
See also: Plants in the Ocean Biome
- Source of Fisheries and Biodiversity
The shallows of mid ocean ridges and seamounts also plays part as areas with high level of biodiversity and fisheries productivity.
The nutrient concentrations in open ocean that are exported downward into the ocean interior because it got restricted and faced a significant fraction of surface will gradually attenuated the depth. It will then support the deep-sea life forms on the abyssal sea floor and also through the water column.
- Provide Energy for Deep Sea Animals
The deep-sea animals live through the energy provided by the hydrothermal vent waters and the heat from the volcanoes. This is because the animals live so deep in the ocean that they live independent of sunlight, thus mining the energy from the deep-sea volcanoes.
The deep-sea animal food chain relies on the microbes that are capable to oxidize the hydrogen sulfide and the other compounds in hydrothermal vent waters. They also convert a large amount of carbon dioxide into organic materials in the sea water through a chemosynthesis process.
The animals included in here consists of many species such as crabs, mussels, vent fish, octopus, clams, and the bizarre giant tube worms which can grow as long as 4 meters.
It is no wonder that those survives here lives independent of sunlight since it is pitch dark, the water pressures in this depth can reach 200 to 300 atmospheres, and earthquakes as well as volcanic eruptions occur frequently here.
- Divergent Plate Boundary
The mid ocean ridge can also be called as the “divergent plate boundary” or also “spreading center”. Every year, the plates will spread apart for about 1 to 20 cm. When the plates move apart, the rock will melt and wells up from about tens of kilometers deep.
Some of the molten rocks will then go up onto the seafloor, making big basalt volcanic eruptions, and therefore, make the longest chain of volcanoes in the world. Meanwhile, the molten rock that doesn’t erupt will freeze onto the plates’ edges as they spread apart.
See also: Unique Characteristics of Pacific Ocean
- Ore Deposits
The hot water in the ocean, which can reach the temperatures of 371 celcius will escape from hydrothermal vents and come in contact with nearly freezing water on the bottom of the ocean. As a result, metals will quickly precipitate.
This makes a surge of black clouds that are actually particle-rich water, or can also be called as black smokers, erupt out of the chimneys that previously deposited solidified mineral. Because there are so many metals spewed out, the hydrothermal vents then will one of the world’s richest ore deposits.
See also: Endangered Species in Pacific Ocean
- Lithospheric Plate
Although it is still debatable, but the lithospheric plate is believed to formed partly because of the separation of the plates that’s done by the ocean ridge. The upwelling is very intense that it is able to throw up the ridge, give an outward force to the plate, then cause subduction at the other ends.
See also: Ocean Animals
Above are the full explanation of the mid ocean ridges, from the types of them, examples of ridges, until the importance of mid ocean ridges themselves. Not that many people know these facts about the mid ocean ridges other than it being the longest mountain range on Earth. Therefore, we hope that this article can help you to discover new things about the mid ocean ridges.