The range of physical phenomena associated with volcanic hazards Volcanic eruptions bring with them a wide range of hazards. This report will describe the different range of risks associated with volcanic activity and discuss possible ways in which the dangers can be avoided. A volcanic eruption can force people from their homes, damage water sources, destroy homes and farms, restrict travel and kill. Pyroclastic flow is a flow of volcanic rock and the most devastating effect of an explosive eruption. A pyroclastic eruption is an eruption in which most of the activity involves fountains or explosions. Nothing in a volcano is as hot and moves with as much power and speed as a pyroclastic flow. A pyroclastic flow begins with rocks and gas being shot up to 20 miles high in a mushroom cloud. Subsequently the column collapses and avalanches of rocks and hot ash form down the mountain. The rocks have the effect of running water as it suffocates everything in its path. Large boulders are carried down the volcano while smaller rocks spin and act like a conveyor belt beneath them. It was a pyroclastic flow that destroyed Pompeii and killed thousands of people in 79 AD. Pyroclastic flows have nothing to do with the slow and predictable movement of lava. Molten rock creeps along the surface but very rarely kills because it is easily overcome. Lava flows have a devastating effect on homes and other structures as they can destroy them very easily. Heavy ashfall spewing from the volcano can make breathing difficult and flatten homes. Ash is especially more dangerous if wet. Volcanicash is material ejected from a volcano in the form of particles and with a diameter of less than 2 mm. Ash can damage crops or force an area into abandonment. Earthquakes can be associated with volcanic activity but are generally small and shallow. Volcanic earthquakes are almost always due to the movement of magma. When a volcano begins to show some unrest, the earthquakes tend to be deep. As the batch of magma moves towards the