The Doom occurred in exactly the year 114 BAL, 112 years before the Targaryen conquest of Westeros began in 2 BAL. Twelve years before the Doom, in 126 BAL, Aenar Targaryen relocated his entire household to Dragonstone , a small volcanic island off the east coast of Westeros. The Targaryens were one of the forty major families of dragonlords in the Valyrian Freehold, though they were not one of the more powerful ones. Aenar was encouraged to flee Valyria by the prophetic dreams of his daughter, which warned of the coming disaster. Along with them the Targaryens took five dragons, who became the only dragons to survive the Doom. Balerion was one of these, but the other four later died through unrevealed circumstances. They did leave eggs behind, however, and from these hatched Vhagar and Meraxes.
Stratovolcanoes tend to form at subduction zones, or convergent plate margins, where an oceanic plate slides beneath a continental plate and contributes to the rise of magma to the surface. At rift zones, or divergent margins, shield volcanoes tend to form as two oceanic plates pull slowly apart and magma effuses upward through the gap. Volcanoes are not generally found at strike-slip zones, where two plates slide laterally past each other. “Hot spot” volcanoes may form where plumes of lava rise from deep within the mantle to the Earth’s crust far from any plate margins.
Eruptions can come from side branches or from the top of the volcano. Some eruptions are terrible explosions that throw out huge amounts of rock and volcanic ash and kill many people. Some are quiet outflows of hot lava . Several more complex types of volcanic eruptions have been described by volcanologists . These are often named after famous volcanoes where that type of eruption has been seen. Some volcanoes may show only one type of eruption during a period of activity, while others may show a range of types in a series.