Volcanoes
When asked the questions of how volcanoes look and work, we give an answer based off of our general knowledge. Yet some research into the functions of volcanoes and different types there are prove they are much more than just lava flowing geological cones. I will be going into focus about the different types of volcanoes and how to tell the differences between active, inactive, and dormant volcanoes. My focus of approach is merely into the research of volcanoes from past to present.
First, I’d like to briefly go over some terms we will be discussing and how to identify the difference between each term. There are a variety of volcanoes that we can identify by physical characteristics.
Let’s begin with Cinder Cone volcanos, (Siebert, Simkin and Kimberly, 2010) the cinder cone volcano can be classified by the small, rough patches of hardened lava. Also called Scoria Cones, these volcanos are the easiest to classify and or the most common type of volcano. When lava is completely filled with gas bubbles it can erupt from a vent under extreme pressure and can have a fire fountain effect which is when the lava shoots directly into the sky. After this process is over, chunks of lava cool fast and land near the vent. Over time, a cone-shaped hill is built up around the crater creating it’s characteristic.
Next, we have the Shield Volcano which usually forms from a lava flow made of fluid basaltic material. Shield volcanos do vary in terms of formation and do not have a set
There are different types of volcanoes, such as shield volcanoes, composite volcanoes, and cinder cone volcanoes that are mentioned in Chapter 9, page 312 of Earth Science. (Refer to figure 2 for volcano type examples.)
A volcano is an earth hazard that occurs on faults between tectonic plates on a destructive boundary and an eruption is a natural disaster. A primary impact happens immediately after the disaster and before any response like death or collapsing or destruction of buildings. A secondary impact occurs later after the disaster, such less farm produce or a reduction in tourism. The severity of these impacts will differ considerably in a MEDC and LEDC where volcanic eruptions have taken place. These may be seen in the Mount St. Helen volcano eruption as well as in the Iceland volcanic eruption. They may also
Anpother factor that can have an impact on the level of hazard posed by a volcano is the type of plate margin on which it occurs. Volcanoes occuring at constructive plate boundaries are usually much less violent than those occuring at destructive plate boundaries. This is because the magma produced by plates moving apart is Basic, and therefoe has a low viscosity, allowing it to flow easily. The lava is produced from a central vent or fissure and erupts regularly but not usually violently. Also,constructive plate boundaries are often found under the sea and create submarine volcanoes, such as along the Mid-Atalntic ridge, so pose few threats to humans. As a result, the hazards posed by volcanoes at constructive plat eboundaries is relatively low. However, the subduction of one plate under another at destrctive plat eboundaries can form an acidic magma chamber, due to the build up of intense heat. Acidic magma is very viscous and resisitant to flow, meaning that there is often a huge build up of pressure, which can result in very violent and dangerous eruptions involving ash and pyroclastic flow. This can pose a a serious hazard. Pyroclastic flowsa are extremely dense, containing toxic gases at very high temperatures, and can move at speeds over 100km/h. The consequences of such an unpredictable hazard can be extremely seruous
The volcanoes are located where there is a divergence or convergence in the tectonic plates and bring their lava from the deepest of the terrestrial mantle. The materials and explosions of these ginates represent a constant risk in the places inhabited by the human being, nevertheless the people ususually live in these areas no matter the risk. On the other hand the volcanos can change the geology of an impressive form, or to cool the temperature of the earth, or to darken the sky. The scientific community increases its efforts to try to understand better what happens in volcanoes, however it is impossible to predict these conditions.
There are many differences between the volcanoes for example the explosivity of the two volcanoes most recent eruptions are completely different Kilauea is almost constantly flowing and has virtually no explosions at all it also has low viscosity lava flows running from it constantly where as MT st Helens is completely different in MT st Helens most devastating eruption in 1980
Volcanoes are one of the most destructive, yet, most beautiful things on Earth. They can make a famous city choke in its own ashes in one day, like Pompeii. Or they can turn a once damaging mountain into a graceful and peaceful home for new life, like Mount St. Helen’s. All volcanoes are unique, and no two are the same. Some erupt differently than others, some look different than others, and all are located in different spots all over the world. I learned this while completing the project and the five volcanoes I researched are examples of my discoveries. The five volcanoes I researched were Mount Hood, Mount Mageik, Long Island, Mount Muria, and Las Pilas.
The location of the volcano is also important. If it is situated on a constructive plate boundary then it is generally less explosive, and therefore poses different threats to volcanoes situated on a destructive plate boundary. The volcano may also be situated on a hotspot like in Hawaii, where the eruptions aren’t very explosive. Volcanos which aren’t explosive can pose other threats to lava flows though, such as dangerous gases being released. Like in Lake Nyos, Cameroon where 1700 people died.
One physical factor which causes differences in a volcanic hazard is the steepness of the volcano. If the volcanoes sides are of a steep gradient then the lava from the volcano would flow must faster than if the sides were a steady gradient. Mount Nyiragongo for
A volcano is defined as a mountain or hill that usually has a cup like crater at the summit. A volcano can be compared to a vent in the earths crust through which lava, ashes and steam are expelled (Volcano, n.d.). There are three main types of volcanoes that scientist have discovered active, dormant, and extinct (howstuffworks.com). Active volcanoes are the ones which have erupted recently, or are expected to blow soon (howstuffworks.com). For example Kilauea volcano on Hawaii is the world’s most active volcano (volcanodiscovery.com). A dormant volcano is one that hasn’t erupted in a long while but has a chance erupt again in the future (howstuffworks.com). Best example there is of a dormant volcano is Mauna Kea which is one of the five mountains that make up the big island of Hawaii (Crain, 2009). And extinct volcanoes are the ones that erupted thousands of years ago and has no possibility of erupting again (howstuffworks.com). An extinct volcano is mount Buninyong which is located in Austria the last time this volcano erupted was a little over ten centuries ago and is now somewhat a tourist attraction.
They are alkalic basalts and very similar to those found from the Raton phase, both chemically and petrographically. ((http://gsabulletin.gsapubs.org/content/80/7/1343.full.pdf) The Capulin Phase includes several different stages, all which occurred during the Pleistocene. All of the Capulin Phase flows are composed of Capulin basalt, which is a fluid lava containing 50% - 55% silica. They have a relatively high percentage of silica for a basalt, because of the presence of quartz grains. These grains came from sedimentary rocks underlying the volcano, e.g. the Dakota Sandstone. The earliest stage of this phase, Mud Hill, formed during a phreatomagmatic eruption, which means that it was driven by the interaction of magma and water, followed by basalt flows. That was approximately 1.7 million 30,000 years ago. The First Series lava flows happened simultaneously as the cinder cone was forming. They flowed east, originating from fissures or series of small vents. The eruption which formed the cone itself, consisted of fissures or several small vents which joined together into one main vent, and the pyroclastic material erupting built up around the vent forming a cone. This eruption lasted for a period of weeks to years, about 55,000 2,000 years ago. The next stage of the Capulin Phase was the Boca eruption. It occurred after the eruption of the main cinder cone had ended, and because the activity shifted from the
What is a volcano: A volcano is a mountain created by the earth. It also creates a hole where molten rock (lava) erupts. A volcano is filled of magma but when the magma erupts and is out of the volcano it is now called lava. When a volcano erupts it fills the air with lava fragments. A volcano can cause a lot of destruction like tsunamis, flash floods, mudflows, rockfalls, and earthquakes. Most volcanoes are located where the tectonic plates meet. Most
Because of all the uncontrolled eruptions that had happened in the past, a daily satellite and real time data from instruments around the volcano give scientists loads of information about the volcano.
The active volcano that I chose to research is Popocatepetl volcano. Popocatepetl volcano is an active volcano located in Mexico. The volcano is oftentimes referred to as “El Popo” by many Mexicans. El Popo is a composite cone volcano. Being a composite cone volcano, El Popo is characterized by a steep cone shape, which was created by many composite layers of material pouring out over numerous eruptions. The lava that comes out of El Popo is extremely viscous. The highly viscous lava does not travel very far, and typically cools down rapidly. Scientists believe that El Popo is about 730,000 years old. It has erupted more than 15 times since 1519. In 1994 El Popo produced gas and ash, which caused nearby towns to evacuate. The toxic
There are many different types of volcanoes in the United States. Composite, Ciner and Shield are the three types of volcanoes. Over the history of Hawaii, covering about 85 million years, there have been 129 volcanoes formed due to the hot spot and of that 129, 123 of them are extinct or seamounts. In Hawaii today, there are currently five active volcanoes, Lo'ihi, Kilauea, Mauna Loa, Hualalai and Haleakala. Lo'ihi is the only underwater volcano in Hawaii; the other four volcanoes are above sea level. Kilauea is a hyperactive shield type volcano. Volcanoes are mainly found where tectonic plates are diverging or converging. The Mid Ocean Ridge is an example of divergent tectonic plates pulling apart, where the Ring of Fire is an example of convergent tectonic plates pushing together. Hawaii today is comprised of many different volcanoes with several different volcano types.
This is only a general overview of the inner workings of volcanoes and their eruptions. For more infomation, visit Volcano World -- The Premier Source of Volcano Info on the Web.