Quiet eruptions are volcanic eruptions that explode gently, with broad sheets of slowly flowing lava. Shield volcanoes, such as those in Hawaii, are commonly associated with quiet eruptions.
In contrast to quiet eruptions, other volcanoes erupt explosively. Mount St. Helens, for instance, spewed lava high in the air when it erupted. Two things control the type of eruption: how much water vapor and other gasses are in the magma and whether the magma is basaltic or granitic. Basaltic magma tends to ooze out gently in a thin, quiet eruption, while granitic magma is thicker and becomes trapped inside the volcano's vents. Once the pressure grows enough to force out the magma, it explodes.Learn More
Mudflow on a volcano is called lahar and is typically caused by heavy rains during or after volcanic eruptions. Lahars can also occur when nearby ice or snow melts, carrying ash and rock debris down a volcano's slopes.Full Answer >
Despite the fact that volcanic eruptions contribute directly to thousands of human deaths each year, they do offer a number of direct and indirect advantages to people. In particular, they aid in plant growth as well as new land formations and building developmentsFull Answer >
A quiet volcano is considered dormant. Dormant volcanoes are volcanoes that have not actively erupted in the past 10,000 years, but still have the potential to erupt at some point.Full Answer >
Basic lava, also called mafic lava, is a type of lava that consists of 50 percent silica. This type of lava is highly fluid and commonly creates large lava flows. Basic lava can reach speeds of up to 20 miles per hour and reach distances of 60 miles.Full Answer >