The territory of the Altai Territory is rather heterogeneous in its geological structure, which is manifested in the high seismic activity of the region. The first records of earthquakes in Altai, documented, date back to the 18th century. Modern seismic activity is characterized by the probability of earthquakes within 8 points.
The concept of "earthquake" and the causes
Any natural phenomenon attracts attention not so much due to little knowledge, but because of its unpredictability. An earthquake is a series of tremors due to shifts of lithospheric plates. In addition, this phenomenon can occur as a result of a careless attitude of man to nature, that is, from nuclear explosions or the collapse of mines.
Quakes often occur at the bottom of the oceans, and this avoids the great catastrophic consequences for populated cities.
Some tremors can only be felt by instruments; others sometimes inflict terrible damage to cities and even countries, while taking with them a huge number of human lives.
Measurement of energy and intensity of seismic vibrations
In order to find out the amount of energy released by underground vibrations, it is necessary to use the Richter scale. It is a classification of earthquakes by magnitude, which are defined in arbitrary units from 1 to 9.5. Oscillation data is obtained using a seismograph that records shifts of tectonic and lithospheric plates.
The intensity of the earthquake is measured on the Mercalli scale and can range from 1 to 12 points. This means that all tremors can be divided into 12 groups, each of which is characterized by the strength of the manifestation of destruction, for example:
- weak shocks;
- moderate tremors;
- strong, and so on.
Do not confuse the measurement of the energy and intensity of earthquakes. The energy becomes known immediately after the acquisition of the seismogram and helps to locate the source of seismic vibrations, and the intensity is the ratio of the magnitude of the vibrations and the activity of the tremors.
Seismically dangerous areas in Russia
Earthquakes occur daily in many locations around the world. Russia was a little luckier in this regard: its territory is located mainly on a single tectonic plate. Nevertheless, in areas such as the North Caucasus and the Kamchatka Peninsula, plate boundaries are clearly marked, as a result of which these regions can be subjected to some tremors.
At the same time, Altai, Eastern Siberia and Yakutia were recognized as the most dangerous and seismically unstable regions. The possible intensity of earthquakes is an average of 4-6 points.
Altai: features and legends
Until some time, the territory of the Altai Territory was relatively stable in seismic terms. But historical documents from 1761 report an incident of enormous power: the magnitude of the oscillations was 8, and the intensity was about 11 points on a modern scale. In addition, traces of ancient changes in tectonic plates were discovered. It was in ancient times that the locals surrounded a haze of mystery with almost any natural phenomenon. According to the book by A. A. Nikonov “Earthquakes … (Past, present, forecast)”, the earthquake in Altai was perceived as “reckless movement of a monster living underground.” Another legend existed during pagan times. It refers to a woman who violated the ban on being present at the sacrifice and caused the dissolution of the union of God with amphibians. The anger of this god was so great that the mountain on which this god lived "shook to the ground."
As can be seen from the above legends, the earthquake in the Altai mountains was perceived in antiquity as a manifestation of discontent of celestials.
XX century
An earthquake in Altai is no longer an extremely rare event. It’s just not always noticeable to people, most of the tremors are recorded only by instruments.
If we consider the period of the XX century, we can find data on strong tremors. Scientific articles mention the phenomenon of the Tsetserlag earthquake. In Altai this incident is far from the only one. In addition to it, many other seismic vibrations with a lower magnitude are given.
We must not forget about the strongest of the known earthquakes of this historical period. It happened in 1965, and its intensity was 7 points. This seismic phenomenon happened near the city of Kamen. Tremors were accompanied by a rumble, and the entire Kamensky district was subjected to significant damage.
The phenomena of modernity
The 21st century has already been remembered by the residents of the Altai Territory. In 2003, there was a strong earthquake. In Altai, it is known as Chuy. Its magnitude was 7.3, and the intensity at the epicenter was 9 points. The consequences of such a seismic shock were landslides, screes and rockfalls. In addition, the so-called mud volcanoes appeared throughout the Chui steppe. Truly impressive was a landslide 1 km wide, which descended on the right bank of the Taltury River. There are opinions that this is far from the most striking thing an earthquake is capable of.
In Altai in August 2016, people with fear were waiting for the promised underground vibrations. According to forecasts, tremors with magnitudes up to 5.0 were indicated during the first ten days of August. EMERCOM of the Russian Federation for the Altai Territory indicated this information on its official website. And indeed, the earthquake in Altai in August 2016 (08/09/2016) really happened. Yes, and not one, but three, and in one day. 225 km south-east of Gorno-Altaysk, the first oscillations of an earthquake in Altai were recorded early in the morning. The forecast began to come true. And in the afternoon, with a difference of one minute, two more tremors were recorded 149 km south and 87 km north-east of Gorno-Altaisk, respectively.
As it turned out later, tremors were due to the proximity of the seismic activity center. Mountain formation has been going on in this region for more than 10 years.
