Type Of Volcano example essay topic

Volcano: A hill or mountain formed around and above a vent by accumulations of erupted materials, such as ash, pumice, cinders or lava-flow. The term refers both to the vent itself and to the often cone-shaped accumulation above it. (Scarth, 1994.) This definition can do Mt. Vesuvius no justice.

Instead, I would describe it as one of the most hellish and population decimating volcanoes. Vesuvius lives... or lived! In its prime, Vesuvius covered and demolished two of Italy's biggest cultural and artistic cities of its time. In this paper, I will be discussing volcanoes in general. In addition, Mt. Vesuvius, in particular, will be thoroughly looked at, as well as its 79 AD eruption.

Volcanoes have long been depicted as nature's killer. In movies, Volcanoes are seen as mountains of fire and spitting lava; their only purpose seems to be to kill and destroy everything in their path. Never is the background of volcanoes discussed. How are volcanoes formed?

Are there different types of volcanoes? What happens during an eruption? The basic questions to aid understanding of volcanoes might change the public's opinion. First, I will begin with the creation of volcanoes. Volcanoes are formed in different ways. In a short version: the earth's plates shift and move.

After the plates collide into each other, one plate is pushed down into the mantel below the crust and melts. Hot magma from the mantle breaks through a weak spot in the crust. As the Ziehm 2 magma shoots out of the crust, the cooling magma called lava becomes hard. After significant time, the hard lava forms a volcanic mountain.

Volcanoes can form in many different sizes and shapes. They can look like a cone, have steep looking flanks, or look as if they were long cracks in the earth's crust. (Plummer et al., 2000). If the mountain is very tall, then there is a greater chance that it was formed from past eruptions. When the lava cools, it makes the mountain bigger and higher.

Depending on the type of volcano, layers can differ in lava / ash content. (Plummer et al., 2000) For example, some stra to and composite volcanoes have alternating ash and lava flow layers. Others have more lava than ash, or more ash than lava; some may consist of 50% ash and 50% lava flow layers. There is a reservoir inside the earth filled with melted rock called magma. (Scarth, 1994) At the top of the reservoir is a tunnel that the magma climbs through to the top. Shapes of volcanoes' cone are described in the next paragraph.

The magma and other volcanic material come out of the cone when the volcano erupts. (Scarth, 1994) An eruption will actually occur when the magma is subjected to pressure. (Rittman, 1976) The magma begins to rise and may overflow in the form of lava. It may also begin to move downwards along the sides of the mountain.

Several shapes of volcanoes are found throughout the world. There are several different types of volcanoes. After reviewing many of them, I decided to write on three major ones. These consist of the shield volcanoes, stra to (composite) volcanoes, and caldera complex volcanoes. Like the ones you may see in Hawaii, shield volcanoes are in the shape of wide plateau mounds. The eruption frequency tends to be very high.

These volcanoes have low-. The lava from Ziehm 3 shield volcanoes is liquid and flows from the crater and the sides of the volcano. (web) Strato volcanoes, also known as composite volcanoes, tend to have violent eruptions and have an intermediate eruption style. These flanks usually are fairly steep and they have layered lava / pyroclastic material. (web). Caldera complexes are usually the most explosive of the Earth's volcanoes. They may not look like a volcano, but their eruption style is so intense that they can end up collapsing on themselves. Yellowstone is probably the most popular of these in the United States.

After giving a basic overview of volcanoes, I feel ready to speak on Mt. Vesuvius. Being known as one of the most dangerous volcanoes in history, Mt. Vesuvius has always been a densely populated and vegetated mountain. It is classified as a complex volcano, so it is an explosive and very steep stra to volcano. Its history begins long before the famous 79 AD eruption.

Located on opposite sides on the volcano are the cities of Pompeii and Herculaneum. Not much is known of Herculaneum; the eruption left the city covered in a thick sheet of lava. Pompeii, on the other hand, which was smothered in ashes, was not as difficult to uncover. Through the uncovering of the ancient city, we find that Pompeii was a thriving tourist spot.

Living rich and lavishly, Pompeiian's enjoyed art and living comfortably. (Morris, 1902) Glorious fountains and statues of gods stood throughout the city. (Morris, 1902) Pompeii seemed to be a city that may possibly have been blind to its surroundings. It was said that the area was plagued with earthquakes. Even so, the city was heavily populated. They must not have known what was in their backyard, or even what was Ziehm 4 lurking around the corner.

On August 4, 79 AD Mt. Vesuvius erupted threw up a rush of smoke, steam, and fire from the volcano's mouth. (Morris, 1902) One side of the valley was blown off, and its rocks, with vast quantities of ashes, burning stones, and sand, were ejected far into the sky. (Morris, 1902) For the next eight days and nights this went on; sulfurous vapors filled the air and violent tremors of the earth were constant. In the end, about ten feet of tephra, rock fragments produced by volcanic explosion, fell on Pompeii. (Plummer et al., 2000) The city was abandoned and as tephra fell, became a forgotten location.

During this chaotic and abrupt explosion a Roman soldier, by the name Pliny, sailed into a nearby port to try and help some of the people fleeting the volcano. His nephew, Pliny the Younger, left us the only account of the great eruption in "Historia Naturalis". This is a retelling of the eye witness account from his letter... (web) My uncle was in command of a fleet of ships that was in a port called Mise num. At about 1: 00 pm on August 24 [79 AD], my mother wanted my uncle to see an unusual cloud. My uncle was resting after having lunch, but he got up right away to look at this cloud.

The cloud appeared to come out of the top of the mountain that was a long way away. The best way to describe it is to say that it looked like a pine tree. It shot straight up like a very tall trunk. At the top of the trunk, the cloud spread out like branches.

Parts of the cloud were very bright, and parts were quite dark. The different colors were caused by the amount of cinders in the different parts of it. My uncle, who was a man of science, thought that this cloud was something that needed investigation. He ordered one of his smaller ships to be readied, and told me that I could go with him if I wanted to. I told him that I needed to finish some work that he had given me. As he was getting ready to go onto his ship, he received a note from Retina, the wife of his friend Bass us.

She was very frightened by the danger that threatened. Her huge house was at the foot of Mount Vesuvius, and there was no way for her to escape except by sea. She begged him to come and save her. So my uncle's expedition changed from a scientific journey to a rescue mission. Ziehm 5 Geology has since named a stage of volcanic eruption after this man. We call this the plin ian stage.

Blanketing large areas with ash, these sustained explosive type eruptions generate high-altitude eruption columns. During the plin ian stage, dust, ashes, cinders, and rocks erupt high into the air. (web) Lasting for hours or even days, no lava flows occur during the plin ian stage. (web) In the nest stage, it only took four minutes for a super hot cloud of steam and mud flowed down the side of Vesuvius and covered the town of Herculaneum. (web) It was estimated that about 3,360 people died in this eruption; ash flows and falls were more than likely the cause. After such a horrific eruption, one must wonder what the volcano has been up to. Since the 79 AD eruption, Vesuvius has erupted a few dozen times. There is some belief in an eruptive cycle that spans from as early as 1631 to 1944.

This long cycle produced heavy tephra falls, major lava flows, and small pyroclastic avalanches that are restricted to the active cone itself. (web heidelberg. de / stud /EGGERTT/. html) From mud and lava flows to ash flows and falls, Vesuvius can produce some of the most dangerous and deadly eruptions. The high population surrounding Vesuvius could be seriously affected by future eruptions. With a sea of houses, hotels, and reforestation flowing down the mountain, realizing the volcano's potential for destruction is a sad reminder of it 79 AD eruption. Ziehm 6 Mt. Vesuvius is just one of several active volcanoes throughout the world. They have wiped out populations in the past and have the potential to decimate more in the future.

Geologists are predicting that a volcanic eruption will occur that will dwarf eruptions such as Vesuvius and Mt. St. Helen's. (web heidelberg. de / stud /EGGERTT/. html) The only thing we can do is sit and wait... nature will take its course. List of RefrencesMorris, C. 1902: The Volcano's Deadly Work: From the Fall of Pompeii to the Destruction of St. Pierre. The Dan Waugh Collection of Nature Books. Washington, D.C. 236-254. Plummer, C.C., Mc Geary, D. & Carlson, D.H., 2000: Physical Geology.

Updated eighth ed... Mcgraw-Hill Companies, Inc., NY. 81-82, 88-89. Rittman, A & L. 1976: Volcanoes. G.P. Putnam's Sons, NY. 20-22 Scarth, A. 1994: Volcanoes: An Introduction. Texas A&M University Press College Station.

56-57, 74,259. [ web web heidelberg. de / stud /EGGERTT/. html].