A Vulcanian eruption is a short, violent, relatively small explosion of viscous magma (usually andesite, dacite, or rhyolite). This type of eruption results from the fragmentation and explosion of a plug of lava in a volcanic conduit, or from the rupture of a lava dome (viscous lava that piles up over a vent). The largest and most violent of all the types of volcanic eruptions are Plinian eruptions. They are caused by the fragmentation of gassy magma, and are usually associated with very viscous magmas (dacite and Vesuvius is a stratovolcano. This vertical aerial photograph shows Vesuvius (bottom), the steep caldera wall of Somma (middle), dark lava flows from the 1944 eruption (north of Vesuvius, against the wall of Somma), and the slope of the former Somma volcano (top). U.S. Navy photograph from Green and Short (1971). Vesuvius is a dangerous and deadly volcano. Mudflows and lava flows from the eruption in 1631 killed 3,500 people. About 3,360 people died in the 79 A.D. eruption from ash flows and falls. Studies of past eruptions and their deposits continue The most common type of volcanic eruption occurs when magma (the term for lava when it is below the Earth's surface) is released from a volcanic vent. Eruptions can be effusive, where lava flows like a thick, sticky liquid, or explosive, where fragmented lava explodes out of a vent. The largest and most violent of all the types of volcanic eruptions are Plinian eruptions. They are caused by the fragmentation of gassy magma, and are usually associated with very viscous magmas (dacite and rhyolite). Volcano Types. The U.S. Geological Survey estimates that there are about 65 active volcanoes in the United States and its territories. The Dynamic maps viewer (shown at right) provides an interactive presentation of potentially active volcanoes in the 48 continguous states. There are two stratovolcanoes, one shield volcano, and one volcano that appears to be formed from overlapping stratovolcanoes. View image with volcano types identified in the Volcanoes Featured Data section. This image was taken by an astronaut of the Expedition 25 crew from the International Space Station. Here are some of the most common types of eruptions: In a Hawaiian eruption, fluid basaltic lava is thrown into the air in jets from a vent or line of vents (a fissure) at the summit or on the flank of a volcano. The jets can last for hours or even days, a phenomenon known as fire fountaining. The largest and most violent of all the types of volcanic eruptions are Plinian eruptions. They are caused by the fragmentation of gassy magma, and are usually associated with very viscous magmas (dacite and rhyolite). In this photographtaken from near the town of Red Bluff, 40 miles west of the volcano, the huge column of volcanic ash and gasproduced by the eruption rises to a height of more than 30,000 feet. (Photograph taken by R.E. On May 22 LassenPeak exploded again in a powerful climactic eruption that blasted rock fragments and pumice high into the air, creating the largerand deeper of the two craters seen near the summit of the volcano today and generating a column of volcanic ash and gas. What type of volcanic eruption is shown in this photograph? A. a lava fountainB. collapse of a volcanic domeC. a fissure eruptionD. a pyroclastic columnE. a volcanic mudflow. A. a lava fountain.  Volcanoes are distinguished by their eruption style, composition, and structure. Volcanoes act differently and form differently because they are made up of different types of rocks and minerals. Below is a description of common volcano types that can be recognized as distinguishable land formations. For more than 200 years keen observers have noted that some volcanic eruptions affect weather and climate. Scientists report that large eruptions at low latitudes can cause the greatest global climate change. There are two stratovolcanoes, one shield volcano, and one volcano that appears to be formed from overlapping stratovolcanoes. View image with volcano types identified in the Volcanoes Featured Data section. This image was taken by an astronaut of the Expedition 25 crew from the International Space Station. Short-term prediction of volcanic eruptions involves monitoring the volcano to determine when magma is approaching the surface and monitoring for precursor events that often signal a forthcoming eruption. 1  Earthquakes-As magma moves toward the surface it usually deforms and fractures rock to generate earthquakes. When magma reaches the surface of the earth, it is called lava. Since it its a liquid, it flows downhill in response to gravity as a lava flows. Different magma types behave differently as lava flows, depending on their temperature, viscosity, and gas content.
http://geology.com/volcanoes/types-of-volcanic-eruptions/ http://volcano.oregonstate.edu/vesuvius http://geology.com/volcanoes/types-of-volcanic-eruptions/ http://ete.cet.edu/gcc/?/volcanoes_types/ http://geology.com/volcanoes/types-of-volcanic-eruptions/ http://pubs.usgs.gov/fs/1998/fs173-98/downloads/fs173-98.pdf http://www.chegg.com/homework-help/type-volcanic-eruption-shown-photograph-lava-fountainb-coll-chapter-6-problem-1mcq-solution-9780077598570-exc http://ete.cet.edu/gcc/?/volcanoes_types/ http://www.tulane.edu/~sanelson/eens1110/volcanoes.htm
what type of eruption is shown in this photograph