On earthquakes and tsunamis are two of the most striking natural phenomena that can affect our planet. Both are closely linked to geological activity and can generate devastating consequences in the affected regions. Although they are often discussed separately, it is important to understand how they are interconnected and how Earth processes influence their occurrence. Learning about natural disasters can give us a better perspective on these phenomena.
What is an earthquake?
Un earthquake, also known as an earthquake or earthquake, is a sudden movement of the Earth caused by the release of Accumulated energy inside. It occurs when the tectonic plates, which make up the Earth's crust, slide or collide with each other due to the accumulation of tension at their edges. Understanding the Tectonic plates is crucial to understanding how these events happen.
The point where the earthquake originates inside the Earth is called hypocenter, while the point on the Earth's surface directly above the hypocenter is called epicenter. Depending on the magnitude and depth of the hypocenter, the effects of the earthquake can vary from slight vibrations to devastating ground displacements. It is interesting to note that understanding the parts of an earthquake helps us to understand its effects.
How is an earthquake measured?
Earthquakes are measured based on two main criteria: magnitude and intensityFor this purpose, scales such as the one used are Judge and of MercalliThe Richter scale measures the energy released by an earthquake in logarithmic terms, while the Mercalli scale assesses the earthquake's effects on structures and people.
the scale of moment magnitude (Mw) It is the most widely used today because it allows even the largest earthquakes to be measured with Greater precisionThe greater the magnitude, the greater the amount of energy released, which can cause greater damage, although this also depends on the depth of the hypocenter and the distance the earthquake is located from inhabited areas. This is also essential for understanding its behavior.
What is a tsunami?
Un tsunami Tsunamis are a series of high-energy waves generated by a sudden displacement of large volumes of water in oceans, seas or even lakes. Unlike wind-generated waves, tsunamis originate due to underwater earthquakes, volcanic eruptions, landslides or meteorite impacts. The nature of a tsunami is fascinating and, to find out more, you can check out how they are form tsunamis in various situations.
Most tsunamis are caused by earthquakes that occurred at the bottom of the sea, especially in regions where there are subduction zones, that is, areas where one tectonic plate sinks under another. This type of movement generates a vertical displacement of water that propagates in the form of waves at high speed. To better understand how it causes a tsunami, it is important to analyze these processes.
The connection between earthquakes and tsunamis
Around the 90% of tsunamis recorded have been caused by underwater earthquakes. When an earthquake occurs under the ocean and causes the seabed to shift, a large amount of water is pushed water up, forming waves that can travel at speeds of up to 800 km/h in the open ocean. This connection between earthquakes and tsunamis It is crucial to understand the most destructive tsunamis of history.
These events can affect coasts located thousands of kilometers from the epicenter of the earthquake. A tragic example occurred in 2004, when a magnitude 9.1 earthquake in the Indian Ocean generated a tsunami which caused the death of more than 230.000 people in different countries. Another notable case was the 2011 tsunami in Japan, which devastated the country's northeast coast following a magnitude 9.0 earthquake. The relationship between the two phenomena reinforces the importance of understanding how these high-impact waves can be triggered.
Areas of greatest risk for tsunamis
The regions most at risk of tsunamis are those located in the Pacific Ring of Fire, an area of great seismic and volcanic activity. Among the most vulnerable areas are Japan, Indonesia, Philippines and the west coast of America. In this context, it is important to study the tsunami in Spain which occurred after the Lisbon earthquake of 1755, as it caused serious damage in Huelva and Cádiz.
There are also records of significant tidal waves in the Atlantic Ocean and the Mediterranean. In Spain, the Lisbon earthquake of 1755 generated a tsunami that severely affected Huelva and Cádiz, causing thousands of deaths. Understanding the areas of greatest vulnerability helps design better prevention and response plans for these phenomena.
Prevention and preparation measures
Although it is not possible to predict exactly when an earthquake or tsunami will occur, there are measures to mitigate its impact:
- On early warning systems They can warn coastal populations with enough time to evacuate.
- The design of resistant buildings to earthquakes reduces the risk of collapse during an earthquake.
- On evacuation plans and education on how to act in the event of a tsunami can save many lives.
The relationship between earthquakes and tsunamis, in particular the , is key to improving protection strategies.
