Category: Volcanoes

Mount Agung Volcanoes

Mount Agung

An active and dangerous volcano on the island of Bali. Article by: Hobart M. King, Ph.D., RPG Mount Agung viewed from the east and rising above the clouds. The caldera rim of Mount Batur is visible in the distance. During the 1963-1964 eruption, pyroclastic flows and lahars roared down these slopes. They traveled all the way to the ocean and killed everyone in their paths.

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Pavlof Volcano Volcanoes

Pavlof Volcano

One of the most active volcanoes in North America is a threat to international and local air traffic. Pavlof Volcano: Ash plume from Pavlof being carried by the wind, May 18, 2013. Photograph by Brandon Wilson. Image from the Alaska Volcano Observatory. Ash Plume from Pavlof's 2007 Eruption Pavlof ash plume: Pavlof volcano and an eruption plume photographed from a commercial flight on August 30, 2007.

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Chaitén (Chaiten Volcano) - Chile Volcanoes

Chaitén (Chaiten Volcano) - Chile

Article by Jessica Ball Picture of a Chaitén Eruption Column Chaitén volcano: View of an eruption column from Chaitén Volcano, Chile, photographed on May 26, 2008. The caldera is about 3 km (1.9 miles) in diameter from rim to rim. The knobby feature between the eruption column and the left rim is part of a lava dome that formed after the 7,400 BC eruption.

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Volcanic Explosivity Index (VEI) Volcanoes

Volcanic Explosivity Index (VEI)

Some volcanic eruptions are thousands, or even a million times more explosive than others. Volcanic explosivity index: The spheres in the illustration above represent the volume of erupted tephra for some of the most widely-known explosive volcanic eruptions. Although most people believe that Vesuvius (79 AD - the Pompeii eruption), Mount St.

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What is a Caldera?   How Do Calderas Form? Volcanoes

What is a Caldera? How Do Calderas Form?

Article by: Hobart M. King, Ph.D., RPG Crater Lake Caldera Crater Lake Caldera: A satellite view of Crater Lake, one of the world's most famous calderas. Crater Lake formed about 7700 years ago when a massive volcanic eruption of Mount Mazama emptied a large magma chamber below the mountain. The fractured rock above the magma chamber collapsed to produce a massive crater over six miles across.

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Novarupta Volcanoes


The Most Powerful Volcanic Eruption of the 20th Century Novarupta map: Approximate location of the June 6th, 1912 eruption. Ash fell on the town of Kodiak for three days, and although the town was about 100 miles from the volcano, it was covered with over one foot of ash which collapsed many buildings.

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Santa Maria Volcano - Guatemala Volcanoes

Santa Maria Volcano - Guatemala

Santiaguito Lava Dome Complex Article by Jessica Ball Picture of Santa Maria Volcano Santa María Volcano with the Santiaguito lava dome complex in the foreground. The erupting dome is El Caliente ("the hot one"). Image copyright Jessica Ball. Larger Image. Santa Maria Volcano: Introduction Santa María, a stratovolcano in the volcanic highlands of southwestern Guatemala, is the site of one of the twentieth century's largest eruptions.

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Kawah Ijen Volcano Volcanoes

Kawah Ijen Volcano

Blue flames and the largest highly acidic lake in the world. Electric blue flames caused by burning volcanic gases and molten sulfur. A night scene at the solfatara in the caldera of Kawah Ijen Volcano. Image copyright iStockphoto / mazzzur. World's Largest Highly Acidic Lake Acid lake: Morning light illuminates the turquoise-colored caldera lake at Kawah Ijen Volcano.

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