Volcanoes/Volcanic activity

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Melting glaciers are causing Iceland to rise and may increase volcanic activity. Credit: Flickr.com/Narisa.

Volcanic activity may be activity from or by a volcano or activity from the sources of volcanoes.

On Iceland this year there is an increase in volcanic activity as shown in the photo on the right.

"Our research makes the connection between recent accelerated uplift and the accelerated melting of the Icelandic ice caps."[1]

"There is actually geological evidence that during the past deglaciation about 12,000 years ago, volcanic activity in some regions of Iceland increased thirtyfold. In fact, some estimate that this uplift could increase the frequency of volcanic eruptions such as the 2010 eruption of Eyjafjallajokull, which had negative consequences worldwide."[2]

Activity[edit]

The Villarrica volcano, near Villarrica in southern Chile, shows some activity on March 4, 2015, a day after it erupted. Credit: Martin Bernetti/AFP/Getty Images.

Def. "the quality or state of [...] causing change"[3][4] is called activity.

"The lava [from the Villarrica volcano on the right] traveled down the slopes of the 9,380-foot high volcano, melting snow along the way and creating mudflows."[5]

Volcanic[edit]

Villarrica volcano erupts on March 3, 2015. Credit: Ariel Marinkovic/AFP/Getty Images.

Def.

  1. of "or pertaining to a volcano or volcanoes",[6]
  2. produced "by a volcano, or, more generally, by igneous agencies",[6] or
  3. changed "or affected by the heat of a volcano"[6]

is called volcanic.

"This is one of the more spectacular volcanic eruptions the world has seen lately [imaged on the right]. Early in the morning on March 3, Villarrica in Chile erupted, sending ash and lava flying some 3,300 feet up into the atmosphere."[5]

"The eruption caused nearly 4,000 people to flee the surrounding areas, including from the nearby tourist town of Pucón, though the BBC reports that residents mostly left "calmly." After about 20 minutes, the volcano piped back down, and the nearby towns seemed okay."[5]

"Villarica is one of Chile's most active volcanoes and, according to the Smithsonian's Global Volcanic Program, is one of three tall stratovolcanoes in a chain that runs perpendicular to the Andes mountain range, believed to be caused by a fracture in the Earth's crust."[5]

Eruption clouds[edit]

Chile's Villarrica volcano can be seen erupting clouds on March 3, 2015. Credit: Aton Chile/AP Photo.

In the photo on the right, Villarrica volcano can be seen erupting clouds on March 3, 2015.

Lava fountains[edit]

Here's a close-up of the lava fountains from the Villarrica volcano. Credit: Ariel Marinkovic/AFP/Getty Images.

On the right is "a close-up of the lava fountains" from the March 3, 2015, eruption of Villarrica volcano in Chile.[5]

"Villarica is one of Chile's most active volcanoes and, according to the Smithsonian's Global Volcanic Program, is one of three tall stratovolcanoes in a chain that runs perpendicular to the Andes mountain range, believed to be caused by a fracture in the Earth's crust."[5]

Lava lakes[edit]

Raging lava occurs in the caldera of the Villarrica volcano in Pucon, Chile. Credit: Barcroft Media/Getty Images.

"Most of the time, though, the volcano is a popular destination for hikers, who climb the 9,380-foot high mountain during the summer months to peer at the lava lake in its crater."[5]

Lahars[edit]

"Because the volcano itself is covered by 15 square miles of glaciers, the lava that flows down the side and mixes with ice and snow to form lahars — a mudflow slurry that can move extremely quickly and destroy towns in their path. According to the Smithsonian, "lahars have damaged towns on Villarica's flanks." The BBC reports that more than 100 people are believed to have been killed by the volcano's mudflows in the past century."[5]

Lightning[edit]

The Villarica volcano erupts near Pucon, Chile, March 3, 2015, with lightning. Credit: Aton Chile/AP Photo.

On the right is an image of the Villarrica volcano erupting near Pucon, Chile, March 3, 2015, with lightning.

Tufa[edit]

These tufa columns are in Mono Lake — Mono County, eastern California. Credit: Vezoy.
Tufa towers in Mono Lake are calcium carbonate spires. Credit: Brocken Inaglory.
These rocks formed under water when calcium-rich spring water at the bottom of the lake bubbled up into the alkaline lake. Credit: Yukinobu Zengame from Cupertino, United States.

Def. "the calcareous deposit of lime found near hot springs"[7] is called tufa.

The image on the right shows Mono Lake's "South Tufa".

"Tufa towers in Mono Lake are calcium carbonate spires and knobs formed by interaction of freshwater springs and alkaline lake water. Tufa can reach heights of 30 ft. (9.1m). Mono Lake is located is Eastern Sierra Nevada and covers about 65 square miles. Throughout the lake's existence of over 1 million years, the steady evaporation of freshwater originally coming from Eastern Sierra streams has left the salts and minerals behind so that the lake is now about 2 1/2 times as salty and 80 times as alkaline as the ocean."[8]

Tuff[edit]

Welded tuff is from Bandelier National Monument, New Mexico. Credit: Andrew Dunn.

Def. a "light porous rock, now especially a rock composed of compacted volcanic ash varying in size from fine sand to coarse gravel"[9] is called tuff.

Hypotheses[edit]

  1. Every 10° of longitude has at least one form of volcanic activity.

See also[edit]

References[edit]

  1. Kathleen Compton (30 January 2015). "Melting Glaciers is Causing Iceland to Rise and May Increase Volcanic Activity". Iceland: Science World Report. Retrieved 2015-03-27.
  2. Catherine Griffin (30 January 2015). "Melting Glaciers is Causing Iceland to Rise and May Increase Volcanic Activity". Iceland: Science World Report. Retrieved 2015-03-27.
  3. "activity, In: Wiktionary". San Francisco, California: Wikimedia Foundation, Inc. 2 February 2015. Retrieved 2015-03-16.
  4. "active, In: Wiktionary". San Francisco, California: Wikimedia Foundation, Inc. 4 January 2015. Retrieved 2015-03-16.
  5. 5.0 5.1 5.2 5.3 5.4 5.5 5.6 5.7 Brad Plumer (4 March 2015). "Chile's recent volcanic eruption looked absolutely stunning — and terrifying". Villarrica, Chile: Vox. Retrieved 2015-03-27.
  6. 6.0 6.1 6.2 "volcanic, In: Wiktionary". San Francisco, California: Wikimedia Foundation, Inc. 13 February 2015. Retrieved 2015-03-16.
  7. "tufa, In: Wiktionary". San Francisco, California: Wikimedia Foundation, Inc. 4 February 2015. Retrieved 2015-03-16.
  8. Mila Zinkova (11 May 2007). "File:Mono lake tufa.JPG, In: Wikimedia Commons". San Francisco, California: Wikimedia Foundation, Inc. Retrieved 2015-03-16.
  9. "tuff, In: Wiktionary". San Francisco, California: Wikimedia Foundation, Inc. 18 February 2015. Retrieved 2015-03-17.

External links[edit]

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