Volcanic Hazards

This article talks about volcanoes and the many types of hazards that are associated with them. All volcanoes are capable of creating a deadly eruption. An element of unpredictability is always present with volcanoes. Scientists are always studying volcano behavior and ways to avoid an eruption. Some different hazards of volcanoes are: lava flows, pyroclastic density currents, pyroclastic falls, lahars, and gases. Lava flows can be very fluid or very viscous. Fluid flows are hotter in temperature and move faster than viscous lava. Viscous flows are not as hot and do not travel as far. These flows can reach temperatures of 1,800 - 3,600 degrees Fahrenheit. Pyroclastic density currents are an explosive eruptive phenomenon. They are a mixture of pulverized rock, ask, and hot gases. A pyroclastic surge is a dilute flow, that usually occurs when magma interacts with water. A pyroclastic flow is a concentrated avalanche of material and usually forms from the collapse of a lava dome. Pyroclastic density currents of any kind are deadly. They can travel at speeds up to 650 mph and can reach 750 degrees Fahrenheit. Pyroclastic falls occur when defragmented rock is ejected from a volcanic vent during an eruption. Lahars are a specific kind of mudflow made up of volcanic debris. They can be caused by melted snow and ice on the volcano when it erupts. Volcanic gases are one of the most deadly components of a volcano. Most of the gas released from an eruption is water vapor, but carbon dioxide, sulfur dioxide, hydrogen sulfide, fluorine gas, hydrogen fluoride, and other gases can be hazardous or even deadly. Volcanoes have many different hazardous effects to them.

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