Which earthquakes can create a tsunami?
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If it is under the bleak ocean, beware of very long, therefore very fast, wave which is low at sea but being long feels ground and starts to build up in height as it enters shallow water and slows down.
Certain earthquakes, known as "tsunamigenic earthquakes," have the potential to generate a tsunami. The characteristics of such earthquakes are determined by several factors:
1. Magnitude: Generally, tsunamis are caused by large-magnitude earthquakes with a Richter magnitude of 7.0 or higher. These quakes produce enough energy to displace a significant amount of water.
2. Depth: Shallow earthquakes occurring near the Earth's surface have a higher likelihood of generating tsunamis. When an earthquake ruptures the seafloor, it vertically displaces the water column above it, resulting in the formation of a tsunami.
3. Subduction zones: The majority of tsunamis are caused by undersea earthquakes along subduction zones. Subduction zones occur where one tectonic plate is forced under another, leading to intense seismic activity and the potential for vertical seafloor displacement.
4. Thrust faulting: Earthquakes that involve thrust faulting, where one tectonic plate is pushed over another, are more likely to generate significant tsunamis. This type of faulting can cause a sudden upward or downward movement of the seafloor, displacing the water column above it.
To summarize, earthquakes with a high magnitude, occurring at shallow depths, along subduction zones, and involving thrust faulting have the potential to create destructive tsunamis. It is important to note that not all earthquakes will produce tsunamis, as the specific circumstances and characteristics need to align for a significant tsunami to form.