Hello butterfly,it have been long since i last posted but i was doing researches for about three weeks and i have come across many researches like submarines earthquakes.
A submarine,undersea, or underwater earthquake is an earthquake that occurs underwater at the bottom of a large water body like an ocean and seas. They are the leading cause of tsunamis. The magnitude can be measured scientifically by the use of the moment magnitude scale and the intensity can be assigned using the mercurial intensity scale
Understanding plate tectonics helps to explain the cause of submarine earthquakes. The Earth's surface or lithosphere comprises tectonic plates which average approximately 50 miles in thickness, and are continuously moving very slowly upon a bed of magma in the troposphere and inner mantle. The plates converge upon one another, and one sub ducts below the other, or where there is only shear stress, move horizontally past each other. Little movements called fault creep are minor and not measurable. The plates meet with each other, and if rough spots cause the movement to stop at the edges, the motion of the plates continue. When the rough spots can no longer hold, the sudden release of the built-up motion releases, and the sudden movement under the sea floor causes a submarine earthquake. This area of slippage both horizontally and vertically is called the epicentre, and has the highest magnitude, and causes the greatest damage.
As with a continental earthquake the severity of the damage is not often caused by the earthquake at the rift zone, but rather by events which are triggered by the earthquake. Where a continental earthquake will cause damage and loss of life on land from fires, damaged structures, and flying objects; a submarine earthquake alters the seabed resulting in a series of waves, and depending on the length and magnitude of the earthquake, tsunami, which bear down on coastal cities causing property damage and loss of life.Submarine earthquakes can also damage sub marine communication cables leading to widespread disruption of the internet and international network in those areas. This is particularly common in Asia, where many submarine links cross submarine earthquake zones such as the pacific ring of fire.
Earthquakes also affect marine life.
Whilst reefs in the South Island of New Zealand were effected, there are not any coral reefs located in this area. However, many places that have earthquakes DO have corals reefs, and these fragile environments can be devastated by an earthquake or Tsunami.
Seismic activity not only lifts the ground, but it also moves it back and forth. This shifting of the ground causes strong water movement and even tsunamis. The combination of rapid water movement and landslides increases the amount of sediment in the water. Sediment eventually settles and can end up covers coral reefs. When sediment covers coral reefs, it blocks the amount of sunlight that the coral absorbs. Coral reefs need sunlight to survive and reproduce.If coral reefs begin to die from the effects of increased sediment from an earthquake, the species that live in the reefs and fish that seek protection and food in the coral reefs will also begin to be affected.
2.Turtles and fish.
Earthquakes affect turtles in multiple ways. Turtles can become stuck in debris left behind by the earthquake or block their path back to the ocean. Increased water levels and even tsunamis have washed away turtle eggs from nesting beaches.Earthquakes cause infrastructure damage. Toxic chemicals such as pesticides and gasoline are at risk of leaking and make their way into the ocean. These toxic chemicals harm fish as well as the food that the fish consume.
The Mangrove root system filters pollutants to maintain the clarity of the water and protect the shoreline from strong waves. A variety of fish, shrimp, crabs, and other species use mangroves to protect themselves from danger.It’s easy to see why the species that thrive within Mangrove forests decline significantly after a tsunami hits coastal areas.
An interview with the new Zealand Herald, Professor Jeff Shims, director of Victoria University’s Coastal Ecology Laboratory stated that The extent of this uplift is not yet clear but without question, the affected areas will experience significant changes in the quantity and composition of marine life. Recovery could take years, and the recovered state could look quite different.
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