It seems that natural disasters happen once every hundred years, and our vacation in one or another exotic country lasts only a few days.

Frequency of earthquakes of different magnitudes in the world per year

• 1 earthquake with a magnitude of 8.0 or higher
• 10 – with a magnitude of 7.0 – 7.9 points
• 100 – with a magnitude of 6.0 – 6.9 points
• 1000 - with a magnitude of 5.0 - 5.9 points

Earthquake intensity scale

Richter scale, points	Force	Description
	Not felt	Not felt
	Very weak tremors	Sensible only to very sensitive people
		Only felt inside some buildings
	Intensive	Feels like slight vibration of objects
	Quite strong	Sensible to sensitive people on the street
		Felt by everyone on the street
	Very strong	Cracks may appear in the walls of stone houses
	Destructive	Monuments are moved from their places, houses are severely damaged
	Devastating	Severe damage or destruction of houses
	Destructive	Cracks in the ground can be up to 1m wide
	Catastrophe	Cracks in the ground can reach more than a meter. Houses are almost completely destroyed
	Catastrophe	Numerous cracks in the ground, collapses, landslides. The appearance of waterfalls, deviation of river flows. No structure can withstand

Mexico City, Mexico

One of the world's most populous cities is known for its insecurity. In the 20th century, this part of Mexico felt the force of more than forty earthquakes, the magnitude of which exceeded 7 points on the Richter scale. In addition, the soil under the city is saturated with water, which makes high-rise buildings vulnerable in the event of natural disasters.

The most destructive earthquakes occurred in 1985, when about 10,000 people died. In 2012, the epicenter of the earthquake was in the southeastern part of Mexico, but vibrations were well felt in Mexico City and Guatemala, about 200 houses were destroyed.

The years 2013 and 2014 were also marked by high seismic activity in different parts of the country. Despite all this, Mexico City is still attractive to tourists due to its picturesque landscapes and numerous monuments of ancient culture.

Concepcion, Chile

Chile's second largest city, Concepción, located in the heart of the country near Santiago, regularly falls victim to tremors. In 1960, the famous Great Chilean earthquake with the highest magnitude in history, magnitude 9.5, destroyed this popular Chilean resort, as well as Valdivia, Puerto Montt, etc.

In 2010, the epicenter was again located near Concepción, about one and a half thousand houses were destroyed, and in 2013 the outbreak sank to a depth of 10 km off the coast of central Chile (magnitude 6.6 points). However, today Concepcion does not lose popularity among both seismologists and tourists.

Interestingly, the elements have haunted Concepcion for a long time. At the beginning of its history, it was located in Penko, but due to a series of destructive tsunamis in 1570, 1657, 1687, 1730, the city was moved just south of its previous location.

Ambato, Ecuador

Today, Ambato attracts travelers with its mild climate, beautiful landscapes, parks and gardens, and massive fruit and vegetable fairs. Ancient buildings from the colonial era are intricately combined here with new buildings.

Several times this young city, located in central Ecuador, two and a half hours from the capital Quito, was destroyed by earthquakes. The most powerful tremors were in 1949, which leveled many buildings and claimed more than 5,000 lives.

Recently, seismic activity in Ecuador has continued: in 2010, an earthquake with a magnitude of 7.2 occurred southeast of the capital and was felt throughout the country; in 2014, the epicenter moved to the Pacific coast of Colombia and Ecuador, however, in these two cases there were no casualties .

Los Angeles, USA

Predicting destructive earthquakes in Southern California is a favorite pastime of geological survey specialists. The fears are fair: the seismic activity in this area is associated with the San Andreas Fault, which runs along the Pacific coast across the state.

History remembers the powerful earthquake of 1906, which claimed 1,500 lives. In 2014, the sun twice survived tremors (magnitude 6.9 and 5.1), which affected the city with minor destruction of houses and severe headaches for residents.

True, no matter how much seismologists frighten with their warnings, the “city of angels” Los Angeles is always full of visitors, and the tourist infrastructure here is incredibly developed.

Tokyo, Japan

It is no coincidence that a Japanese proverb says: “Earthquakes, fires and father are the most terrible punishments.” As you know, Japan is located at the junction of two tectonic layers, the friction of which often causes both small and extremely destructive tremors.

For example, in 2011, the Sendai earthquake and tsunami near the island of Honshu (magnitude 9) led to the death of more than 15,000 Japanese. At the same time, Tokyo residents have already become accustomed to the fact that several minor earthquakes occur every year. Regular fluctuations only impress visitors.

Despite the fact that most buildings in the capital were built taking into account possible shocks, residents are defenseless in the face of powerful disasters.

Repeatedly throughout its history, Tokyo disappeared from the face of the earth and was rebuilt again. The Great Kanto Earthquake of 1923 turned the city into ruins, and 20 years later, rebuilt, it was destroyed by large-scale bombing by American air forces.

Wellington, New Zealand

The capital of New Zealand, Wellington, seems to be created for tourists: it has many cozy parks and squares, miniature bridges and tunnels, architectural monuments and unusual museums. People come here to take part in the grandiose Summer City Program festivals and admire the panoramas that became the film set for the Hollywood trilogy The Lord of the Rings.

Meanwhile, the city was and remains a seismically active zone, experiencing tremors of varying strength from year to year. In 2013, just 60 kilometers away, a magnitude 6.5 earthquake struck, causing power outages in many parts of the country.

In 2014, Wellington residents felt tremors in the northern part of the country (magnitude 6.3).

Cebu, Philippines

Earthquakes in the Philippines are a fairly common occurrence, which, of course, does not frighten those who like to lie on the white sand or snorkel in clear sea water. On average, more than 35 earthquakes with a magnitude of 5.0-5.9 points and one with a magnitude of 6.0-7.9 occur here per year.

Most of them are echoes of vibrations, the epicenters of which are located deep under water, which creates the danger of a tsunami. The 2013 earthquakes claimed more than 200 lives and caused serious damage in one of the most popular resorts in Cebu and other cities (magnitude 7.2).

Employees of the Philippine Institute of Volcanology and Seismology are constantly monitoring this seismic zone, trying to predict future disasters.

Sumatra Island, Indonesia

Indonesia is rightfully considered the most seismically active region in the world. The westernmost one in the archipelago has become especially dangerous in recent years. It is located at the site of a powerful tectonic fault, the so-called “Pacific Ring of Fire.”

The plate that forms the floor of the Indian Ocean is being squeezed under the Asian plate here as quickly as a human fingernail grows. The accumulated tension is released from time to time in the form of tremors.

Medan is the largest city on the island and the third most populous in the country. Two major earthquakes in 2013 seriously injured more than 300 local residents and damaged nearly 4,000 homes.

Tehran, Iran

Scientists have been predicting a catastrophic earthquake in Iran for a long time - the entire country is located in one of the most seismically active zones in the world. For this reason, the capital Tehran, home to more than 8 million people, was repeatedly planned to be moved.

The city is located on the territory of several seismic faults. An earthquake of magnitude 7 would destroy 90% of Tehran, whose buildings are not designed for such violent elements. In 2003, another Iranian city, Bam, was destroyed by a 6.8 magnitude earthquake.

Today Tehran is familiar to tourists as the largest Asian metropolis with many rich museums and majestic palaces. The climate allows you to visit it at any time of the year, which is not typical for all Iranian cities.

Chengdu, China

Chengdu is an ancient city, the center of the southwestern Chinese province of Sichuan. Here they enjoy a comfortable climate, see numerous sights, and become immersed in the unique culture of China. From here they travel along tourist routes to the gorges of the Yangtze River, as well as to Jiuzhaigou, Huanglong and.

Recent events have reduced the number of visitors to the area. In 2013, the province experienced a powerful earthquake with a magnitude of 7.0, when more than 2 million people were affected and about 186 thousand houses were damaged.

Residents of Chengdu annually feel the effects of thousands of tremors of varying strength. In recent years, the western part of China has become especially dangerous in terms of seismic activity of the earth.

What to do in case of an earthquake

• If an earthquake catches you on the street, do not go near the eaves and walls of buildings that may fall. Stay away from dams, river valleys and beaches.
• If an earthquake strikes you in a hotel, open the doors to freely leave the building after the first series of tremors.
• During an earthquake, you should not run outside. Many deaths are caused by falling building debris.
• In case of a possible earthquake, it is worth preparing a backpack with everything you need for several days in advance. A first aid kit, drinking water, canned food, crackers, warm clothes, and washing supplies should be at hand.
• As a rule, in countries where earthquakes are a common occurrence, all local cellular operators have a system for alerting customers about an approaching disaster. While on vacation, be careful and observe the reaction of the local population.
• After the first shock there may be a lull. Therefore, all actions after it must be thoughtful and careful.

Recently I helped my son with a short report on this topic. Despite the fact that I know enough about this phenomenon, the information I discovered turned out to be extremely interesting. I will try to accurately convey the essence of the topic and talk about How are earthquakes classified?. By the way, my son proudly brought an A from school. :)

Where do earthquakes occur?

First you need to understand what is commonly called an earthquake. So, scientifically speaking, these are strong vibrations on the surface of our planet, caused by processes that occur in the lithosphere. Areas where high mountains are located are places where this phenomenon occurs most often. The thing is that the surfaces in these areas are at the stage of formation, and the cortex is most mobile. Such areas are called places rapidly changing terrain, however, many earthquakes were also observed on the plains.

What types of earthquakes are there?

Science identifies several types of this phenomenon:

• tectonic;
• landslide;
• volcanic.

Tectonic earthquake- a consequence of the displacement of mountain plates, which is caused by the collision of two platforms: continental and oceanic. This species is characterized by formation of mountains or depressions, as well as surface vibrations.

Regarding earthquakes volcanic type, then they are caused by the pressure of gases and magma on the surface from below. Usually the shocks are not very strong, however can last quite a long time. Typically, this species is a harbinger of a more destructive and dangerous phenomenon - volcano eruptionA.

Landslide earthquake occurs as a result of the formation of voids that can be formed by the movement of groundwater. In this case the surface just collapses, which is accompanied by small tremors.

Intensity measurement

According to Richter scale it is possible to classify an earthquake based on the energy it carries seismic waves. It was proposed in 1937 and over time became widespread throughout the world. So:

1. not felt- shocks are absolutely not detected;
2. very weak- is registered only by devices, a person does not feel it;
3. weak- can be felt while in the building;
4. intense- accompanied by slight displacement of objects;
5. almost strong- felt in open spaces by sensitive people;
6. strong- felt by all people;
7. very strong- small cracks appear in the brickwork;
8. destructive- serious damage to buildings;
9. devastating- huge destruction;
10. destructive- gaps up to 1 meter are formed in the ground;
11. catastrophic- buildings are destroyed to the foundation. Cracks more than 2 meters;
12. catastrophe- the entire surface is cut with cracks, the rivers change their channels.

According to seismologists - scientists who study this phenomenon, about 400 thousand happen per year earthquakes of varying strengths.

Volcanic eruptions are often accompanied by strong earthquakes. But earthquakes can occur without volcanic activity. However, these phenomena pose a serious threat. There are many cases where earthquakes and volcanic eruptions led to casualties and the destruction of entire cities.

Do such phenomena occur in Russia?

To understand whether Russia can be classified as a group of countries where earthquakes and volcanic eruptions occur, it is necessary to understand the causes of such phenomena:

• earthquakes are the results of shifting tectonic plates. These are large-scale processes that occur deep underground, but are felt on its surface. Earthquakes are accompanied by tremors, and volcanic eruptions are accompanied by the release of volcanic lava;
• Volcanic eruptions can only occur in mountainous areas. After all, any volcano is a mountain. Accordingly, areas where there are no mountains cannot become the site of volcanic eruptions. They are possible only in mountain ranges. Meanwhile, most of the territory of Russia is occupied by a plain with small hills;
• There are several mountain ranges in Russia. All of them were formed as a result of ancient volcanic eruptions that occurred many millions of years ago. Active volcanic processes are still occurring in Kamchatka. For example, Mount Belukha is an active volcano.

Thus, Russia is one of the countries where earthquakes and volcanic eruptions occur.

Are there still volcanoes in Russia

The main mountain ranges of Russia are the Caucasus, Ural Mountains, and the Sayan Range. These mountains do not have active volcanoes. All volcanoes have already ceased their activity. For example, the so-called “sleeping” volcano is Mount Elbrus, the highest point in Europe.

Thus, there are no longer any threats from seismic or volcanic activity in Russia. The only place where such processes continue is Kamchatka. Therefore, most of the territory of Russia is completely safe in terms of the risk of earthquakes or volcanic eruptions.