Volcano

• Volcanoes are Earth's geologic architects, creating more than 80 percent of our planet's surface and allowing life to thrive.
• Lava rivers spread into bleak landscapes, forming an opening in Earth’s crust.
• Pyroclastic materials are thrown out.
• Bombs are clumps of rocks with lava.
• Volcanic Ash is less than 1cm.
• Lapili is more than 2cm.
• Blocks are huge solid rocks.
• Diverging is when plates rip apart causing volcanic activity and shallow earthquakes, an example is the Mid-oceanic Ridge (Mid-Atlantic Range).
• Converging occurs when one plate dives or “subducts” beneath the other, resulting in a variety of earthquakes and a line of volcanoes on the overriding plate, an example is the Pacific Ring of Fire or Circum Pacific belt.
• The most destructive volcanoes include Mt. Tambora, which had the largest volcanic eruption in 500 years, and Mt. St. Helens, the most disastrous volcanic eruption in U.S. history.
• Mt. Tambora erupted sending volcanic ash 40km into the sky, its elevation reached more than 4,300 meters (14,100 feet) high, making it one of the tallest peaks in the Indonesian archipelago.
• Krakatoa is a caldera in the Sunda Strait between the islands of Java and Sumatra in the Indonesian province of Lampung, it is also a larger caldera.
• A caldera is a large, usually circular-like bowl volcanic depression formed when magma is withdrawn or erupted from a shallow underground magma reservoir.
• Novarupta Alaska was formed during the largest volcanic eruption of the 20th century, Novarupta released 30 times the volume of magma of the 1980 eruption of Mount St. Helens.
• Mt. St. Helens is the most disastrous volcanic eruption in U.S. history, it killed 57 people, destroyed 200 homes, 47 bridges, 15 miles (24 km) of railways, and 185 miles (298 km) of highway.
• Mt. Pinatubo is the world's largest volcanic eruption to happen in the past 100 years, it occurred on June 15, 1991, and formed an opening in Earth’s crust.
• Magma Chamber is a hollow within the volcano.
• Region deep within the Earth’s crust.
• Composite volcanoes have a steep profile.
• Mount Pinatubo is an active stratovolcano in the Zambales Mountains, located on the tripoint boundary of the Philippine provinces of Zambales, Tarlac and Pampanga, all in Central Luzon on the northern island of Luzon.
• A volcanologist is someone who studies about volcanoes.
• Conduits are passageway tubes of the volcano, serving as the throat like of the volcano.
• Volcanology is the study of volcanoes.
• Hotspot is an area of the Earth's mantle from which hot plumes rise upward, forming volcanoes on the overlying crust.
• Dormant volcanoes have not erupted in a long time but are expected to erupt again in the future.
• Slopes are the lands where lava passes through, measured by the angle made by the lower flank of the volcano and the peak of the volcano.
• Shield volcanoes are formed from many magma flows of low viscosity.
• Vents are the main openings on the surface of the volcano.
• Its eruptive history was unknown to most before the pre-eruption volcanic activity of early 1991.
• Shield is a type of volcano named for its low profile, resembling a shield lying on the ground, it is a broad volcano with shallow inclining sides.
• Composite, also known as Stratovolcana Cone, are tall, symmetrically shaped, with steep sides, sometimes rising 10,000 feet high, they are built of alternating layers of lava flows, volcanic ash, and cinders.
• Active Erupting volcanoes are those that are currently erupting.
• Cinder Cone is the simplest type of volcano, built from particles and blobs of congealed lava ejected from a single vent.
• Crater is a bowl-shaped depression, or hollowed-out area, produced by the impact of a meteorite, volcanic activity, or an explosion.
• Active Dormant volcanoes are not erupting at the moment but are considered “active” because they could erupt in the future.
• Samoa is composed of a linear chain of volcanic islands situated atop the Pacific tectonic plate.
• Volcanic Gas is released after volcanic eruptions.
• Pinatubo was heavily eroded and obscured from view by dense forests which supported a population of several thousand indigenous Aetas.
• Lava dome is a type of composite volcano with lava.
• Lava is composed of water vapor, carbon dioxide, and sulfur, it is a magma inside the volcano.