Preview

The Volcano

Good Essays
Open Document
Open Document
810 Words
Grammar
Grammar
Plagiarism
Plagiarism
Writing
Writing
Score
Score
The Volcano
hiiiLava domes are built by slow eruptions of highly viscous lavas. They are sometimes formed within the crater of a previous volcanic eruption (as in Mount Saint Helens), but can also form independently, as in the case of Lassen Peak. Like stratovolcanoes, they can produce violent, explosive eruptions, but their lavas generally do not flow far from the originating vent.
Cryptodomes

Cryptodomes are formed when viscous lava forces its way up and causes a bulge. The 1980 eruption of Mount St. Helens was an example. Lava was under great pressure and forced a bulge in the mountain, which was unstable and slid down the north side.
Volcanic cones (cinder cones)
Main articles: volcanic cone and Cinder cone

Volcanic cones or cinder cones result from eruptions of mostly small pieces of scoria and pyroclastics (both resemble cinders, hence the name of this volcano type) that build up around the vent. These can be relatively short-lived eruptions that produce a cone-shaped hill perhaps 30 to 400 meters high. Most cinder cones erupt only once. Cinder cones may form as flank vents on larger volcanoes, or occur on their own. Parícutin in Mexico and Sunset Crater in Arizona are examples of cinder cones. In New Mexico, Caja del Rio is a volcanic field of over 60 cinder cones.

Based on satellite images it was suggested that cinder cones might occur on other terrestrial bodies in the Solar system too; on the surface of Mars and Moon.[3][4][5]
Stratovolcanoes (composite volcanoes)
Cross-section through a stratovolcano (vertical scale is exaggerated):
1. Large magma chamber
2. Bedrock
3. Conduit (pipe)
4. Base
5. Sill
6. Dike
7. Layers of ash emitted by the volcano
8. Flank 9. Layers of lava emitted by the volcano
10. Throat
11. Parasitic cone
12. Lava flow
13. Vent
14. Crater
15. Ash cloud
Main article: Stratovolcano

Stratovolcanoes or composite volcanoes are tall conical mountains composed of lava flows and other ejecta in alternate layers, the

You May Also Find These Documents Helpful

  • Satisfactory Essays

    Geology Chapter 5

    • 580 Words
    • 3 Pages

    Shield volcanoes form when the products of eruption have low viscosity and are weak, so they do not pile up but spread. They are broad, gentle does that resemble a solder’s shield. Cinder cones are cone shaped piles of basaltic lapilli and blocks. Strato-volcanoes are large; cone shaped and is made of interleaved layers of lava, tephra and volcaniclatic debris. The prefix of its name emphasizes that they can grow to be kilometers high.…

    • 580 Words
    • 3 Pages
    Satisfactory Essays
  • Better Essays

    Script For Mt St Helens

    • 1103 Words
    • 5 Pages

    Coupled with these episodes were hundreds of small bursts or explosions of gas and steam. Mt. St. Helens has had four major eruptions and lots of minor ones. Volcanoes erupt due to the pressure of the magma and earth, and then erupts if a plate moves. Here is an image of the volcano before and after the eruption in…

    • 1103 Words
    • 5 Pages
    Better Essays
  • Good Essays

    They are built from particles and blobs of congealed lava ejected from a single vent.…

    • 963 Words
    • 4 Pages
    Good Essays
  • Better Essays

    Pompeii Research Paper

    • 1091 Words
    • 5 Pages

    Volcanoes are formed on land near coastal areas when a continental plate and an oceanic plate converge. The oceanic plate submerges, due to its higher density, and is pushed deeper and deeper beneath the surface. The high temperature and pressures below melt the rock which creates hot, buoyant magma. Ultimately this magma rises towards the surface and accumulates in a reservoir, known as the magma chamber. The eruption occurs when the pressure within in the chamber surpasses the pressure of the upper rock, magma forces its way through the cracks in Earth’s crust. Magma that is low in gas and silicon dioxide produces thin quickly spreading lava which has a low viscosity, while a magma that is heavily composed of gas and silicon dioxide will yield a thick, viscose magma. The thicker magma builds up and because of this pressure, will cause a large…

    • 1091 Words
    • 5 Pages
    Better Essays
  • Powerful Essays

    Volcanologists have named four stages of volcanic activity, Ape Canyon, Cougar, Swift Creek, and Spirit Lake. These stages are separated by dormant intervals. Little is known about the Ape Canyon stage (300-35 thousand years ago) (ka). During this stage, lava domes in two distinct periods, one from 300 to 250 thousand years ago (ka) and a second from 125-35 ka. Geologists have found layers of ash and rocks that were changed hydrothermally,…

    • 2731 Words
    • 11 Pages
    Powerful Essays
  • Good Essays

    As www.marinebio.net states, Wailea-Makena, Hawaii, East Maui County was caused by a hotspot or an extra hot plume of molten rock. This happens when heat rises as a thermal cloud from inside of the Earth. Heat and pressure at the bottom of the tectonic plate forces magma to form which then rises through cracks and erupts to form volcanoes. As volcanoes move away from a hotspot, they start to erode and become inactive. Maui is the third oldest volcano of the main Hawaiian islands and could still erupt one more time. Haleakalā or the East Maui Volcano is also a shield volcano or a broad, domed volcano with sloping sides. It forms more than 75% of the Hawaiian Island of Maui and has an alert level of “normal.” The last time Maui erupted was in the 17th century, but even so, the soil is still very fertile from it’s past eruptions. Thanks to this fertile soil, crops such as coffee, macadamia, papaya, tropical flowers, sugar and fresh pineapple grow here.…

    • 559 Words
    • 3 Pages
    Good Essays
  • Good Essays

    Overview To all the residents in the village of Boomsdale, recently Dr. Bigbrain with the United States Geological Survey (USGS) has detected small earthquakes coming from Mt. Thunder. For those of you that do not yet know, Mt. Thunder is an active stratovolcano and these earthquakes could be related to an impending volcanic eruption. There are three types of volcanos which include: shield volcanos, scoria cone volcanos, and stratovolcanoes. Unfortunately, stratovolcanoes are the most dangerous, explosive, and deadly volcanoes. The reason for stratovolcano’s explosive tendency is because of the type of magma contained in the volcano’s magma chamber located underground beneath Mt. Thunder.…

    • 753 Words
    • 4 Pages
    Good Essays
  • Good Essays

    First, we will discuss Mount St. Helens Volcano. Mount St. Helens is a stratovolcano located in the Pacific Northwest of the United States within Washington State. A stratovolcano is also known as a composite cone, which is “a large symmetrical structure that consists of alternating layers of explosively erupted cinders and ash interspersed with lava flows (Lutgens, 2012.)” Due to the cone shape of the volcano, stratovolcanoes are known for creating large explosive eruptions that can eject vast amounts of pyroclastic material. Mount St. Helens is a part of the Pacific Ocean Ring of Fire that spans across the ocean along the shorelines of continents that are located along the ocean. Within the Ring of Fire the mountain range which Mount St. Helens is a part of in the United States is called the Cascade Range. Of the 13 active volcanoes that are a part of the Cascade Range, Mount St. Helens is one of the more active volcanoes with its last major eruption occurring in May 1980 (Lutgens, 2012.)…

    • 395 Words
    • 2 Pages
    Good Essays
  • Good Essays

    Lava Pit In Hawaii

    • 323 Words
    • 2 Pages

    One time in Hawaii, in 1888, there was a small village just next to a little beach. Not far from the village, there was a huge “lava pit.” Scientists believed that it was just a volcano that had formed underground and only the opening at the top could be seen from the surface. The lava pit had always been filled with lava, and people wondered if it would ever erupt.…

    • 323 Words
    • 2 Pages
    Good Essays
  • Good Essays

    Mauna Loa is a shield volcano, but it can develop into a cinder cone. It has had 33 eruptions and in most of the eruptions, an earthquake has preceded the eruption. The most famous eruptions occurred in 1950 and 1984. On June 1, 1950, lava erupted from a 20 km long fissure along the middle portion of the rift zone.…

    • 685 Words
    • 3 Pages
    Good Essays
  • Good Essays

    yellowstone

    • 407 Words
    • 2 Pages

    A supervolcano is any volcano capable of producing a volcanic eruption with an ejecta volume greater than 1000 km cubed. This is about 1000 times bigger than a normal volcanic eruption. super volcanos don’t tend to be visible from the ground as they are so big. This is because the caldera, a large volcanic crater, are so big, in the case of Yellowstone it is over 40 miles across, so people do not recognize it as a volcano. Super volcanos occur when magma in the mantle rises into the crust from a hotspot but is unable to break through the crust, due to this pressure builds in a large and growing magma pool until the crust is unable to contain the pressure, this is what will and is happening at the Yellowstone caldera. These can also be formed at convergent plate boundaries, this is what is happening at Toba.…

    • 407 Words
    • 2 Pages
    Good Essays
  • Satisfactory Essays

    * Volcanoes are grouped according to their shapes and Mount Vesuvius is a stratovolcano. Stratovolcano is a term given to volcanoes which have a pointed shape, shaped due to the deposits of volcanic ash, asphalt, hardened lava etc.…

    • 310 Words
    • 2 Pages
    Satisfactory Essays
  • Good Essays

    Mt Etna

    • 886 Words
    • 4 Pages

    An eruption begins when pressure on a magma chamber forces magma up through the conduit and out the volcano's vents. When the magma chamber has been completely filled, the pressure in the pipe will build up very high resulting in an explosion. When magma reaches earth's surface it is called lava. It may pour out in gentle streams called lava flows or erupt violently into the air. Rocks ripped loose from the inside of the volcano or torn apart by the gas may be shot into the air with the lava. These rocks are blown out of a volcano and are called volcanic bombs. Along with these bombs dust, ash, lava and cinder are released into the air. Volcanic activity is classified by how often a volcano erupts. A volcano may be active, dormant, or extinct. Active volcanoes erupt constantly. Dormant volcanoes are inactive, but not long enough to determine whether they will erupt again or not. Extinct volcanoes have been inactive since the beginning of recorded history.…

    • 886 Words
    • 4 Pages
    Good Essays
  • Good Essays

    Cinder-Cone Volcanoes release little lava and have very loud explosions. The main threat of these volcanoes is the large amounts of pyroclastic materials building up inside.…

    • 1102 Words
    • 5 Pages
    Good Essays
  • Powerful Essays

    A volcano can be a mountain like structure or a wide sloping hill that opens downwards to a pool of molten rock below the surface of the earth. When a break in the earth’s surface allows molten rock material to come up from the earth’s core, a volcano is formed. Volcanic eruptions can cause lateral blasts, lava flows, hot ash flows, mudslides, avalanches, falling ash and floods. These eruptions can also trigger tsunamis, flash floods, earthquakes, mudflows and rock falls. Examples of volcanic mountains are Mount St. Helens, Mount Fuji, and Pinatubo. (Kusky, 2010).…

    • 3334 Words
    • 14 Pages
    Powerful Essays

Related Topics