cause large flows tend to advance more rapidly then do small flows. Other hazards include airborne particles of ash, cinder, and fragile strands of volcanic class called Pele’s hair, and corrosive volcanic gasses. Volcanic gasses are emitted during all types of eruptions. A common gas produced during Hawaiian volcanoes that is potentially harmful to human health is sulfur dioxide. Even small concentrations of sulfur dioxide can combine with water to form sulfuric acid, which can attack skin, cloth, metal and other materials. The greatest danger associated with the explosive eruptions is their potential to produce pyroclastic surges. These surges are highly destructive, turbulent gas clouds that flow rapidly along the ground carrying hot ash and rock fragments. These eruptions are generally caused by the interaction of magma and ground water. The magnitude of the resulting steam explosion varies from harmless to catastrophic. Ground cracks and settling is also commonly associated with volcanic activity; both generally occur near active or recently active volcanic vents as the result of shallow underground movement of magma. Cracking of the ground precedes the beginning of an eruption as magma is forcefully injected into the area. The hazard presented by ground cracks and settling associated with eruptions, is usually limited to areas near the activity. Man-made structures that escape other damages from an eruption, however, can be damaged or destroyed by cracking, tilting, or setting of the ground beneath them. Ground cracks will remain after the eruption is over and can pose a threat to unwary people and animals if the cracks are obscured by heavy vegetation (USGS).In conclusion, the Hawaiian Islands are made up of a chain of volcanoes that began to from more then seventy million years ago. Many of these volcanoes formed the islands that have subsided and eroded beneath sea level, and some of the old volcanoes probab...
