Lesson 04: Volcanic Eruption





The video I found is of Mount Tavurvur erupting in 2014. The eruption captured in this video is an explosive one. The lava is not just flowing out, there is some pressure built up which leads to the explosion. The video also captures the sound burst which I thought was very cool. 
Image result for tavurvur on mapMount Tavurvur is an active volcano in Papua New Guinea and is considered to be quite dangerous. It is a cinder cone. I think it is fairly new, but I am unsure and couldn't find the age of it. Cinder cones are built from ejected lava fragments that begin to harden in flight. It is relatively small at a height of 223 meters, with steep sides and a characteristic crater. (Map from http://www.dailymail.co.uk/sciencetech/article-2747577/Holy-smokes-Watch-explosive-moment-volcano-erupts-triggers-SONIC-BOOM-sending-shockwaves-sky.html)
Image result for tavurvur
from https://www.washingtonpost.com/news/capital-weather-gang/wp/2014/09/03/
nasa-satellite-captures-incredible-extent-of-tavurvur-volcano-ashfall/
Tavurvur is a sub-vent of the Rabaul caldera and is the most active volcano in that caldera. The caldera Rabaul violently exploded in 1994 and destroyed the island's largest city and since then Mount Tavurvur is showing the most activity in that caldera.This graphic is from NASA and shows the ashfall from the most recent eruption of Tavurvur, pictured to the left.    While we don't have anything quite that exciting happening locally, we do have two volcanic tuff cones nearby, the Menan Buttes, pictured below. These were formed about 10,000 years ago when magma ran into an aquifer and the hot magma was explosively fragmented. Overall, volcanos are awesome! No matter if the explosion is effusive or explosive, it is definitely a powerful thing to see, even if it's just through video.
Image result for menan buttes
from http://trailrunner.com/event/spitfire-ultra-trail-challenge-at-menan-butte/

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