Earthquakes are one of the most destructive natural disasters that can occur anywhere in the world. They are caused by the movement of tectonic plates, which make up the Earth’s crust. The tectonic plates are constantly moving and shifting, causing stresses and strains to build up.
When the energy released by these stresses and strains exceeds the strength of the rocks, the result is an earthquake. The frequency of earthquakes can vary greatly depending on a number of factors, including the location and geological activity of tectonic plate boundaries, the presence of geological faults, and human activities such as underground excavation and fracking.
The location and geological activity of tectonic plate boundaries are the primary factors that determine the frequency of earthquakes in a given area. Tectonic plate boundaries are the areas where two or more plates come together and interact. These boundaries can be divergent, meaning the plates are moving apart, or convergent, meaning the plates are moving towards each other. Earthquakes are most common along convergent plate boundaries, where two plates are colliding and causing stress and strain to build up.
These kinds of boundary zones are seismic belts, and they include the Pacific Ring of Fire, the Alpide Belt, and the Mediterranean-Himalayan Belt.
In addition to tectonic plate boundaries, the presence of geological faults also influences the frequency of earthquakes. A fault is a crack or break in the Earth’s crust, and it can occur anywhere along a tectonic plate boundary.
When two plates move against each other along a fault, stress, and strain build-up, and when the energy released by these stresses and strains exceeds the strength of the rocks, the result is an earthquake. There are several types of faults, including normal faults, reverse faults, and strike-slip faults. Normal faults occur when two plates move apart from each other, and reverse faults occur when two plates move toward each other. Strike-slip faults occur when two plates move horizontally past each other.
Human activities can also influence the frequency of earthquakes. Underground excavation, such as mining, can cause stress and strain to build up in the rocks, leading to the potential for earthquakes. Additionally, fracking, or hydraulic fracturing, is a process used to extract natural gas and oil from the Earth’s crust. This process involves injecting large amounts of water, sand, and chemicals into the ground at high pressure, which can cause the rocks to break and shift.” This causes small earthquakes referred to as “induced earthquakes.”
Human activities that can cause earthquakes include:
- Underground excavation, such as mining, which can cause stress and strain to build up in the rocks.
- Dams and reservoirs, which can cause changes in the pressure and water levels in the ground and lead to earthquakes.
- Deep underground disposal of waste, which can cause stress and strain to build up in the rocks.
- Geothermal energy production, which involves pumping water into hot rock formations deep underground, which can cause stress and strain to build up in the rocks.
The perception of the increased frequency of earthquakes can also be influenced by improved detection technology and increased global communication. In the past, earthquakes were often underreported due to a lack of accurate detection technology and limited communication between countries. However, with the advent of modern technology, it is now possible to detect and report earthquakes much more accurately, leading to a better understanding of the frequency of earthquakes and the impact they have on communities.