what is a unconfined aquifer
What Is A Unconfined Aquifer? Unconfined aquifers are w...
Volcanic eruptions produce three types of materials: gas, lava, and fragmented debris called tephra.
The style of eruption depends on a number of factors, including the magma chemistry and content, temperature, viscosity (how runny the magma is), volume and how much water and gas is in it, the presence of groundwater, and the plumbing of the volcano.
Mount Everest is not an active volcano. It is not a volcano but a folded mountain formed at the point of contact between the Indian and Eurasian…
We consider two defining characteristics of these phreatic eruptions to be (1) the dominance of hydrothermally altered or lithic components in the eruptive products and (2) the involvement of exogenous water (i.e., steam/water not immediately exsolved from melt).
geothermal energy
Volcanoes are the main source of geothermal energy.Feb 24, 2015
Hazards from quiet lava flows include igniting fires and producing chlorine-rich gas clouds where lava pours into the sea. Since 1980, as many as five volcanoes have erupted each year in the United States. Eruptions are most likely to occur in Hawaii and Alaska.
What causes an eruption to be explosive? A volcano erupts explosively if its magma is high in silica. … In a quiet eruption, the magma is low in silica, allowing the magma to flow out gently. In an explosive eruption, the magma is high in silica, which causes the magma to be thick and sticky.
Two important factors control whether an eruption will be explosive or quiet. One factor is the amount of water vapor and other gases that are trapped in the magma. The second factor is how much silica is present in the magma.
Volcanic eruptions may be subtle or explosive and can produce dangerous lava flows, poisonous gases, and flying rocks and ash. Many volcanic eruptions are also accompanied by other natural hazards, such as earthquakes, landslides, debris flows, flash floods, fires and tsunamis.
According to information found on the International Tsunami Information Center website, violent volcanic eruptions, although relatively infrequent, represent impulsive disturbances, which can displace a great volume of water and generate extremely destructive tsunami waves in the immediate source area.
Eruptions, and subsequent erosional processes, can deliver vast quantities of sand and gravel to rivers on or near volcanoes. Mobilized material can move rapidly as voluminous slurries of rocks and debris (lahars) that can destroy structures along their path and deposit vast quantities of sediment along a valley floor.
Kilauea, Stromboli and Mount St. Helens are all considered active, as are volcanoes such as Pacaya and Redoubt. A dormant volcano is one that is “sleeping” but could awaken in the future, such as Mount Rainier and Mount Fuji. … Kohala on the Big Island of Hawaii could be considered an extinct volcano.
Even dormant volcanoes are becoming active and not only that, but also extinct volcanoes are coming back to life. An extinct volcano by definition is dead volcano, which has not erupted in the last 10,000 years and is not expected to ever erupt again.