Volcanic eruptions are one of the natural disasters that can occur not only on land but also beneath the ocean. Why is it that the ocean, filled with seawater, cannot extinguish underwater volcanoes?
How Volcanoes Work
The formation of volcanoes is related to the structure of the Earth. According to current human understanding, the Earth has multiple layers like an onion, with the core at the center. Although the temperature of the core can reach over 5000 degrees Celsius, which could melt any material, the immense pressure keeps the molten substances compressed into solid form.
Outside the core is the mantle, and above the mantle is the crust. The temperature of the crust is relatively low, while the temperature of the core is high; thus, the mantle undergoes thermal convection, forming a viscous liquid state. If there are cracks in the tectonic plates as they collide or separate, the mantle can be released along these cracks, leading to volcanic eruptions.
Volcanoes can form and erupt beneath the ocean floor. (Image: Sohu).
During a volcanic eruption, molten material exceeding 1000 degrees Celsius bursts to the Earth’s surface. While seawater can lower the temperature of magma, it cannot prevent volcanic eruptions, because the principle behind volcanic eruptions is due to extremely high internal pressure, which seawater cannot reduce. The combustion process requires fuel, and water can isolate fuel and lower temperatures. Due to the different formations of volcanoes and fires, seawater cannot extinguish underwater volcanoes.
When an underwater volcano erupts, magma continuously erupts from within, accumulating in the seawater, raising the surrounding terrain and forming a volcanic cone. In the 1960s, residents near Iceland in the North Atlantic witnessed an underwater volcanic eruption, which caused seawater to shoot hundreds of meters into the sky, with a large amount of volcanic ash reaching several kilometers high.
After the volcanic eruption ended, an island was formed in the area, about 40 meters wide and 550 meters long. Numerous volcanic eruptions contributed to the formation of the island of Surtsey, which is also the youngest island in the world. Only scientists in sterile clothing are permitted to visit to study and observe life on the island.
The Impact of Volcanoes
For many, volcanoes only bring disaster. However, in reality, volcanoes also bring some precious metals to the Earth’s surface, such as diamonds. The main component of diamonds is carbon. While carbon is not rare on Earth, diamonds are relatively rare. This is because the formation of diamonds is inseparable from high temperature and high pressure conditions. The mantle meets these conditions for diamond formation, which is why most diamonds are formed in the mantle.
Volcanic eruptions also bring some precious metals to the Earth’s surface.
With volcanic eruptions, diamonds located in the mantle are brought to the Earth’s surface, which is why diamond mines today are concentrated in areas that have experienced volcanic eruptions.
In addition to diamonds, volcanoes also affect the Earth’s climate. A volcanic eruption releases a large amount of ash into the atmosphere; the higher the volcanic eruption, the more volcanic ash is produced. Volcanic ash reflects sunlight like clouds and prevents sunlight from reaching the Earth’s surface, leading to a drop in temperature. The eruption of Mount Tambora in 1815 caused global climate change, resulting in the Year Without a Summer (1816), which devastated crops worldwide.
After a period, the carbon dioxide released from volcanic eruptions will dominate, causing the Earth’s temperature to rise again.
In many cases, after large-scale volcanic eruptions, the negative impacts on life on Earth can last for a long time, potentially leading to mass extinction.
