Recently, in the town of Boomdale, there have been several earthquakes. A investigative team from the USGS, the United States Geological Survey group, have arrived in Boomdale and set up a base camp to monitor these earthquakes. Their urgency in this matter is due to the fact that the believe these recent earthquakes could be related to something much bigger, an eruption from the volcano at Mt. Grumble. The small village of Boomdale is located about 15 km east from the volcano, nestled in a valley. After interviewing with the head scientist of the USGS, there is a strong belief that this volcano is due to erupt within the next couple of months.
We want to inform the inhabitants of Boomdale so that everyone is equipped with the correct information about Mt. Grumble and its destructive capabilities if it were to erupt. First off, Mt. Grumble is located in the Cascade Range, containing many other destructive volcanoes as well, such as Mt. Rainier and Mt. St. Helens. Most of the volcanoes in this region are Stratovolcanoes. A stratovolcano is the most explosive of the volcanoes, and therefore the most dangerous. There are a couple tell tale signs that let us know it ‘s a stratovolcano. For example, its shape. Stratovolcanoes typically have gentle lower slopes with steep upper slopes, which is exactly the shape of Mt. Grumble. These volcanoes are also mostly associated with subduction zones. Most active volcanoes on Earth are associated with subduction at convergent plate boundaries. These volcanoes also have high viscosity, the ability to resist flow, so the magma that erupts from these volcanoes are more explosive and therefore more dangerous. Stratovolcanoes also tend to produce plinian eruptions, which are the most dangerous of the eruptions.
There are several other characteristics of Mt. Grumble that are concerning and allow us to believe that an eruption can be very deadly. For example, Mt. Grumble is covered on top by a cap of glacier ice and pristine snow. The presence of this increases the risk of a lahar, otherwise called a volcanic mudflow. They form when volcanic ash and debris become saturated with water and begin to flow down slope. There are multiple ways that this can happen. One of the ways is when large amounts of ice and snow melt during the eruption. Since Mt. Grumble has both ice and snow, it is very likely to experience a lahar when it erupts. Lahars are very dangerous and can cause a lot of damage and be deadly to those in its path because they are very rapid and have the consistency of wet concrete. Along with Mt. Grumble, other stratovolcanoes in the Cascade Region are covered with ice and snow and therefore are susceptible to future lahars. Boomdale should be aware of this because they are located in the valley along the volcano ‘s flank, which is where lahars travel along.
Not only can erupting lavar turn into a lahar, but it can also turn into pyroclastic material, or tephra. Pyroclastic fall is the term used when talking about pyroclastic material that falls to the ground during a volcanic eruption. Tephra is when erupting lava cools into the air and turns into solid volcanic fragments and then fall to the ground. These fragments are known as ash (smallest), lapilli, and blocks/bombs (biggest). Blocks and bombs fall out close to the volcano because they are the heaviest, so they aren ‘t as much of a danger to the people of Boomdale because they aren ‘t located that close to the actual volcano. While lapilli fragments are smaller and carried a little farther, it ‘s the ash that is most worrisome for the town of Boomdale. Ash are very small and are the only fragments that are carried up into the ash cloud. High atmospheric winds can carry this ash cloud great distances. Also, in a Plinian eruption, most of the material is ash sized, so this eruption would most likely produce a lot of ash that can be carried to to the town of Boomdale. The ash cloud of the eruptive column spreads out in the high atmosphere (~20,000-40,00 ft.) by the high atmospheric winds. One example that we can see from this is the eruption of Mt. St. Helens in 1980 which was carried eastward by the jet stream as far east as the Atlantic Ocean. Since Mt. Grumble is very similar to Mt. St. Helens, we can assume that the same thing could happen when Mt. Grumble erupts. Wet ash can cling to roofs, and then cause collapse, which is something everyone should keep in mind. But the most worrisome is the respiratory problems that breathing in this ash can cause for the people exposed to it.
Not only is pyroclastic fall a problem, but so is pyroclastic flow. Pyroclastic flow is a fluidized mixture of solid to semi-solid fragments along with hot gases that flows down the flank of a volcano and along valleys. This is very toxic and dangerous because they are extremely hot and move very fast like avalanches, over 10o mph. They are the most deadly of all volcanic phenomena. While we don’t want to scare the people of Boomdale, we want to make it known that this is a big deal and needs to be taken seriously. For example, Maurice and Katia Krafft were renown filmmakers of volcanic phenomena. They had probably seen more volcanoes erupt than anyone else in the world. They were well educated on the subject and were well aware of the dangers. In 1991 at the eruption of Mt. Unzen in Japan, Maurice and Katia Krafft lost their lives along with 43 other people because they underestimated the size of the pyroclastic flow. For this reason we would like to stress the fact that these eruptions are unpredictable and can be very deadly. Stay up to date with the news and be ready to evacuate if told to do so. Do not underestimate these volcanoes. Even very well educated and experienced volcanologists like the Kraffts weren ‘t able to predict the severity of a volcanic eruption, so it ‘s always best to evacuate and play it safe.
Disclaimer: This essay has been submitted by a student. This is not an example of the work written by our professional essay writers. You can order our professional work here.
Sorry, copying is not allowed on our website. If you’d like this or any other sample, we’ll happily email it to you.
Your essay sample has been sent.
Want us to write one just for you? We can custom edit this essay into an original, 100% plagiarism free essay.Order now