"Sky News" stated that some studies and research confirmed the existence of 3 types of earthquakes that strike many places on Earth's surface. He relied on the studies to classify them on how they were formed and on the geological forces that lie in the rocks and tectonic plates adjacent to the earth's crust.
These types of earthquakes:
Tectonic earthquakes:
The main reason is tectonic and terrestrial movements, and these tectonic movements occur at plate boundaries.
Volcanic earthquakes:
They occur in conjunction with volcanic activity and as tectonic plate pressure increases, forcing magma to move underground.
Synthetic earthquakes:
They are caused by the impact of human activities, such as nuclear or chemical explosions, and land mines that cause seismic waves.
Shallow earthquakes at a depth of 70 km:
There is another classification of earthquakes according to depth, including shallow earthquakes, which occur at depths of less than 70 km.
Medium earthquakes at a depth of 300 km:
In addition to a second type, which are “intermediate earthquakes,” which occur at depths between 70 and 300 kilometers.
Deep earthquakes at a depth of 700 km:
As for deep earthquakes, which are the last in the classification according to depth, they occur at depths ranging from 300 to 700 km.
Earthquake ratings:
Earthquakes are classified according to 3 scales: the Richter scale, the Mercalli scale, and the magnitude scale.
Classification of earthquakes according to the Richter scale:
The Richter scale is one of the widely used methods for measuring the strength of earthquakes, thanks to the scientist Charles Richter who introduced it in 1934.
This scale is based on the amplitude of the largest wave recorded by a specific type of seismograph, as well as the distance between the epicenter and the measuring device.
Seismologists use the Richter scale to express the seismic energy released by an earthquake.
Classification of earthquakes according to the Mercalli scale:
Another method used to measure the intensity of earthquakes is the Mercalli scale, developed by Josep Mercalli in 1902.
This scale relies on the observations and observations of people who felt the earthquake in order to estimate its intensity, and therefore it is indicated that it is not a scientific scale like the Richter scale, as people may exaggerate their description and estimate of the intensity of the earthquake. It is also possible that the witnesses did not agree on a single opinion of what happened, so the amount of damage caused by the earthquake may not accurately describe its magnitude.
There are many factors that affect the amount of damage caused by an earthquake, including the design of buildings, the distance from the epicenter, in addition to the nature of the surfaces on which the structures are built, whether they are rocky or earthy.
The intensity of an earthquake is expressed according to the Mercalli scale in Latin numbers, gradually increasing, starting from the least damaging to the highest.
Classification of earthquakes according to the magnitude scale:
The moment scale is one of the scales that are preferred to be used and applied at the global level to express the strength of earthquakes, as it is concerned with measuring a larger range of earthquakes.
Because many other scales such as the Richter scale do not provide accurate estimates of earthquakes of large magnitude and impact, this scale is abbreviated as (MW).
It is based on the total moment of the earthquake, which is equal to the product of multiplying the distance moved by the fault by the force required to move it, and is derived by seismological recordings at several stations.
Estimates of the Richter scale and the magnitude scale for small and large earthquakes are almost similar, except that the magnitude scale is the only scale capable of accurately reading an earthquake of magnitude 8 or greater, and there is no upper limit for it.