There have been 1 1 earthquakes of magnitude 8 in history, which not only caused great damage to human beings and the natural environment, but also took decades for the local area to fully recover. These earthquakes are:
1, Chile earthquake, earthquake intensity 9.5. It happened in the waters of central Chile, and caused tsunami and volcanic eruption. The earthquake killed 5,000 people and left 2 million homeless. This earthquake is the highest in history.
2. Indonesia 9.0 earthquake. It happened in Aceh province, Sumatra, Indonesia. The tsunami triggered by the earthquake swept through Sri Lanka, Thailand, Indonesia and India, leaving about 300,000 people missing or dead.
3. Japan earthquake, magnitude 9.0. The earthquake occurred in the Pacific Ocean east of Miyagi Prefecture, and was felt in China, Shanghai and Beijing. Triggered a tsunami. The earthquake caused serious damage to Japan's economy and caused many deaths and disappearances.
4. The earthquake in Alaska, USA, with an earthquake intensity of 8.8 degrees. The tsunami caused 125 deaths and property losses of 3 1 1 billion dollars. Strong earthquakes were felt in most parts of Alaska, Yukon, Canada and Colombia.
5. Ecuador earthquake (190665438+1October 3 1) with earthquake intensity of 8.8. It happened off the coast of Ecuador and Colombia. The earthquake triggered a strong tsunami, resulting in more than 1000 deaths. Shocks were felt along the coast of Central America, San Francisco and Japan.
6. Chile earthquake (February 27th, 20 10) with earthquake intensity of 8.8. The scope of damage caused by this earthquake is relatively small, and the death toll is not much, but it is undoubtedly a heavy disaster for a country like Chile.
7. Alaska earthquake (1March 9, 957), with an earthquake intensity of 8.7. It happened in the waters near Andrea Island and Unac Island in Alaska, USA. The earthquake led to the eruption of Vesivedov volcano, which had been dormant for 200 years, and triggered a tsunami with a height of 15 meters, which spread as far as Hawaii Island.
8. Great earthquake in Russia (1952165438+1October 4th), with an earthquake intensity of 8.7. The tsunami triggered by the earthquake spread to the Hawaiian islands, but no casualties were caused.
9. Indonesia earthquake (March 28th, 2005), with an earthquake intensity of 8.7 degrees. The epicenter was located in the waters north of Sumatra Island, Indonesia, not far from the place where the 9.0-magnitude earthquake occurred three months ago. Did not cause a tsunami.
10, Alaska earthquake (1February 4, 965), earthquake intensity 8.7. The earthquake triggered a tsunami as high as 10.7 meters, which swept the whole Sumatra island.
1 1, China Tibet earthquake (1August 950 15), with earthquake intensity of 8.5. More than 2000 houses and temples were destroyed. The Yarlung Zangbo River in China and the Brahmaputra River in India were the worst hit, with at least 1.500 deaths.
Earthquake magnitude is divided into nine grades, namely:
1. Generally, earthquakes with magnitude less than 1 are called ultrashort earthquakes.
2.M≥ 1 and less than 3 are called weak earthquakes or microseisms. This kind of earthquake is generally not easy to detect if the source is not very shallow.
3, M≥3, less than 4.5 is called a felt earthquake. People can feel this kind of earthquake, but generally it won't cause damage.
4.M≥4.5 and less than 6 are called moderate earthquakes. It belongs to an earthquake that can cause damage, but the degree of damage is also related to many factors such as focal depth and epicentral distance.
5. M≥6 and less than 7 are called strong earthquakes.
6, M≥7, less than 8 is called a major earthquake.
Earthquakes of magnitude 7, 8 and above are called major earthquakes.
Conclusion: When an earthquake happens, we ordinary people must keep calm and don't rush to avoid disaster. This will not only make us safe, but also make our lives more dangerous. We must obey the guidance of science, so as to minimize the harm.