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Out of all natural disasters, volcanoes are often the most deadly.
Spewing ash, smoke, sulfur, and lava, entire cities can be lost
to one eruption. Still, many scientists are willing to risk the
danger in order to find out more about these fire spitting mountains. Most of the volcanoes in the world appear upon the border of tectonic plates. Volcanoes can ford here in two different ways. The first way is when one plate slides under another. When two plates collide, one plate is lifted up. Simultaneously, the other plate is forced under the first. The plate that was pushed under is melted into a pocket of magma. These pockets may later be the source of a volcanic eruption. In the second way, two plates split apart. As they pull away from each other, hot lava oozes up through the gap between the ground. This forms round, smooth rocks of lava called pillow lava. The other way a volcano can erupt is if it is located over a hot spot. Though scientists aren't sure why, some stationary spots in the mantle have very high temperatures. As land passes over these spots, it sometimes melts the rock of the crust there. Since the plates are always moving, hot spots often cause more that one volcano to erupt. All of the islands in the Hawaiian chain were caused by one hot spot. In fact, the Hawaiian islands are still growing due to frequent explosions. One of the most famous volcanoes in history is Mount Vesuvius. This legendary volcano is the one that destroyed the ancient Roman cities of Pompeii and Heraculaneum. Vesuvius blew its top in about A.D. 79, bringing ruin to both cities. While the remains of Heraculaneum are not very distinct, many things were found still intact in the town of Pompeii. There have been carbonized figs and walnuts, bowls of petrified eggs, and even carbonized bread that still had the baker's stamp seen on it! In Heraculaneum, some houses have been found, but there have not been very many bodies. Scientists concluded that most of the people evacuated the town before the deadly gases hit. Despite all of the disasters they create, volcanoes can also do some good for the environment. They spread natural fertilizer to the ground through the ash, which is full of nutrients and minerals. Any amount of ash from a volcano less than 8 inches can considerably help their crop. Unfortunately, too much ash will cause the plants to wither and die. Even though volcanoes can do the land good, their destruction far often outweighs the help they give. Scientists are still puzzled about many things about volcanoes. In fact, there are probably many things scientists will never be able to understand about volcanoes. Still, we have already uncovered a lot of information about these lava gushing mountains. As the Hawaiian Islands continue to grow, so does our knowledge of volcanoes. Hopefully, there will not be many devastating ones in the near future, but we should always be prepared! |
