On August 24, 79 CE, Mount Vesuvius erupted. Mount Vesuvius is a volcano in what is today western Italy. The Roman resort towns of Pompeii and Herculaneum were devastated by the two-day event, one of the most famous and deadly in European history.The eruption occurred in two phases. In the first phase, Mount Vesuvius spewed a giant column of volcanic gas, volcanic ash, and rock high into the atmosphere. A type of rock called pumice rained down on towns surrounding the volcano. The harsh rain of pumice injured people who were outdoors and clogged roads, doorways, and drains. The rocks built up to a height of about 2.5 meters (8.2 feet). The build-up became so heavy that it collapsed roofs on homes and businesses, crushing or trapping people inside. This phase, called a Plinian eruption, lasted nearly a day.The second phase was even more destructive. This phase was characterized by pyroclastic flows. A pyroclastic flow is a very fast-moving current of volcanic gas and ash rushing down the side of a volcano. Some of the gases flooding Pompeii and Herculaneum were toxic, and may have included hydrogen sulfide and carbon monoxide. Many residents of Pompeii who were unable to evacuate during the first phase of the eruption suffocated during the second phase. Even more victims burned to death, as the gases reached temperatures of up to 300 degrees Celsius (570 degrees Fahrenheit), “enough to kill hundreds of people in a fraction of a second,” according to one volcanologist.Mount Vesuvius is still an active volcano. In fact, it is considered one of the most dangerous volcanoes in the world. Its last major eruption was in 1944.
Term Part of Speech Definition Encyclopedic Entry active volcano Noun
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.
Encyclopedic Entry: atmosphere characterize Verb
to describe the characteristics of something.
to fall apart completely.
strong, vertical support structure, such as a pillar.
steady, predictable flow of fluid within a larger body of that fluid.
Encyclopedic Entry: current destructive Adjective
to explode or suddenly eject material.
to leave or remove from a dangerous place.
number expressed as a ration, such as a/b.
stage in a process or transformation.
Plinian eruption Noun
powerful, violent volcanic explosion characterized by pyroclastic flows and ejection of material high into the atmosphere.
type of igneous rock with many pores.
pyroclastic flow Noun
current of volcanic ash, lava, and gas that flows from a volcano.
Encyclopedic Entry: pyroclastic flow resort Noun
facility or space people go to relax in a luxury setting.
natural substance composed of solid mineral matter.
to eject or discharge violently.
to be unable to breathe.
degree of hotness or coldness measured by a thermometer with a numerical scale.
Encyclopedic Entry: temperature toxic Adjective
volcanic ash Noun
fragments of lava less than 2 millimeters across.
Encyclopedic Entry: volcanic ash volcanic gas Noun
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.
Encyclopedic Entry: volcano volcanologist Noun
scientist who studies volcanoes.