Mount Fuji is an example of an extrusive volcanic landform which are tall, very steep, and consists of the rock type of basalt, and this type of rock makes up the oceanic crusts according to About.com website. This is unusual because Mount Fuji is specifically a composite volcano or Strato volcano, and the rock mineral that makes up this type of volcano is andesite which is granitic crustal rocks and magma. Also, gases dissolve from andesite rocks during eruptions when it's mixed with the magma From this process, the ash cloud is formed containing the composition of various gases which are extensive and hazardous, and if you do breathe it, you can die from it. Other hazards that can take are tephra fall, pyroclastic flow, etc.
The largest hazards for Mt Fuji are: Tephra and Pyroclastic flows. For the Mt Fuji eruption in 1707, the Tephra which is a lava fragments and gas carried in an ash cloud spreaded mostly to the eastern foot of Mt Fuji which destroyed villages and many inhabitants died from starvation according the documents from the department of Geosystem Sciences from Nihon University. As for the Pyroclastic flows during the eruption in 1707, which are avalanches of hot rock, gas, and ash also took part in the destruction of the villages in the eastern part of Japan.
Mt Fuji was formed by subduction which is the process of two moving tectonic plates converge into each other, this motion causes the lithosphere of one plate to move underneath the other plate. Another effect of subduction, the plate that is underneath is melted due to the pressure. According to the website geocraft.com, the main process of how a volcano is formed is when the oceanic crust collides with the continental crust, and the upper mantle lithosphere of the oceanic crust sinks underneath the continental crust, which then melts into magma.
You can found more information on Mount Fuji and other volcanoes from this weblinks:
Courtesy of Pacifics Island Travel.com
Courtesy of Mount Fuji--Geology
Hey John, nice work on your first blog entry. The external links were very beneficial in helping to learn even more about volcanoes. Apart from a few minor grammer errors, this blog entry was very interesting. One topic I would like to see you elaborate on more is the actual forming of the volcano. For example, what techtonic plates were involved in the forming of Mt. Fuji, and are their any craters or caulderas present? Also Since Mt. Fuji is often convered in snow, another form you could mention is a Lahar (a mudflow created by lava melted high mountain icecaps). In all, good work I am excited to read the next one!
ReplyDelete-MATTHEW WELCH