Details of the Eruption:
Mount Fuji is 60 miles South-West of Tokyo on Honshu Island, Japan. The latest eruption was in December 16, 1707, where in the first day 72 houses, were destroyed in Subassiri town 10 km away from the volcano. This eruption did not harm any people, but it did follow a harmful Earthquake known as the Hoei Earthquake which happened in November of 1707. The eruption lasted 16 days, ending on January 1st, 1708. Today there is concern about a possible reawakening of the volcano.
Description of the Physical Environment:
Mount Fuji is one of the 3 Holy Mountains along with Mount Tate and Mount Haku.
Type of Volcano: Mount Fuji is a stratovolcano that is formed from excessive explosive eruptions at subduction boundaries. At this subduction boundary the Philippine plate subducts under Japan. Stratovolcanos have alternating layers of lava flows and pyroclastic materials. They can have either quiet or explosive eruptions with any lava type. Mount Fuji has mostly basaltic lava. Basaltic lava is high in iron and magnesium, it has a low viscosity (resistance to flow) , it has a high melting temperature, a low gas content, quiet eruptions (rarely explosive), and located over oceanic hot spots and Mid-Ocean ridges. Stratovolcanos tend to have many vents including cinder cones, and domes found low on all sides of the volcano. The elevation of Mount Fuji is about 3,776 meters (12,390 feet). Mount Fuji has an almost equilateral shape, a form that is found almost nowhere else on Earth. Why does a volcano form here? Stratovolcanos form at subduction boundaries, oceanic hot spots, and mid-ocean ridges. At mid-ocean ridges, two plates pull apart and cause sea-floor spreading, rift valleys, and earthquakes. At subduction zones between oceanic and continental plates, the oceanic plate (which is more dense) subducts under the continental plate, this process causes convection recycling, trenches, volcanic mountain ranges, and earthquakes. Finally, at a hot spot magma is pushed up into the interior of a plate. Over time the hot spot stays still while the plate moves over it. |
Eyewitness reports/ Interviews
First Interview: "It all started with the 8.4 magnitude earthquake in October followed by a smaller earthquake and a tsunami. Then on December 16th the eruptions started. By the end of the first day, many people had lost their homes. The volcano didn't stop until 16 days later."
Second Interview: "I woke up on December 16, 1707, to the house shaking. I woke my husband, and we ran outside to see what was happening. As soon as we realized that the volcano by our home was erupting we ran inside for shelter. We waited here until we couldn't hear anything else, and went to look out the window. The road outside our home was covered with volcanic ash."
Second Interview: "I woke up on December 16, 1707, to the house shaking. I woke my husband, and we ran outside to see what was happening. As soon as we realized that the volcano by our home was erupting we ran inside for shelter. We waited here until we couldn't hear anything else, and went to look out the window. The road outside our home was covered with volcanic ash."
Igneous Rocks Associated with Mount Fuji
Pumice, a very light and porous volcanic rock formed when a gas-rich lava solidifies rapidly, is one of the igneous rocks associated with Mount Fuji.