Mount Fuji is an active volcano that last erupted in 1707.
Photograph by Melville B. Grosvenor, National Geographic
On December 16, 1707, scientists recorded the last confirmed eruption of Mount Fuji, Japan’s highest point. Fuji is composed of several overlapping volcanoes. The top two are known as “Old Fuji” (Ko Fuji) and “Young Fuji” (Shin Fuji). Fuji has erupted at various times starting around 100,000 years ago—and is still an active volcano today.
Fuji’s last eruption ejected tons of tephra into the atmosphere. Tephra includes all solid volcanic material—not lava or volcanic gas. Tephra released by the 1707 eruption of Fuji (called the Hoei eruption) included volcanic ash and volcanic rock, such as pumice and scoria. Tephra blanketed the city of Edo (now the central part of Tokyo, more than 100 kilometers (62 miles) away).
Japan is located on the most geologically active part of the planet, the Ring of Fire. The roughly horseshoe-shaped Ring of Fire circles the South Pacific, the eastern rim of Asia, and the western edge of the Americas. This region is known for its volcanic eruptions and earthquakes. Japan is no exception. Fuji’s Hoei eruption was preceded by a massive earthquake. The estimated-8.6-magnitude earthquake likely triggered a primed Fuji to erupt.
The damage—especially the deaths—from these disasters, plus a tsunami, is hard to untangle. But what can be attributed to the Hoei eruption is the damage to homes near Fuji. The tephra fallout also reduced agricultural productivity in the region, causing many people to starve to death.
volcano that has had a recorded eruption since the last glacial period, about 10,000 years ago.
layers of gases surrounding a planet or other celestial body.
large settlement with a high population density.
to establish the truth or accuracy of a statement.
result or outcome of an action or situation.
harm that reduces usefulness or value.
to get rid of or throw out.
release of material from an opening in the Earth's crust.
molten rock, or magma, that erupts from volcanoes or fissures in the Earth's surface.
landmass that forms as tectonic plates interact with each other.
type of igneous rock with many pores.
to preserve observations with notes, drawings, photographs, audio or video recordings.
to lower or lessen.
any area on Earth with one or more common characteristics. Regions are the basic units of geography.
person who lives in a specific place.
type of rough, crusty volcanic rock.
to die from lack of food.
solid material ejected from a volcano during an eruption.
fragments of lava less than 2 millimeters across.
gas such as water vapor or carbon dioxide that is released into the atmosphere by a volcano.
an opening in the Earth's crust, through which lava, ash, and gases erupt, and also the cone built by eruptions.
scientist who studies volcanoes.