Myths and Facts about Volcanoes

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Diana Pho
Geology 104
11/27/04
Homework #6

                        The Myths and Facts about Volcano

        Through watching Volcano, the general public may be misguided about the
geological truth mixed in with Hollywood fiction. There are many misrepresentations
about volcanoes and eruption activity in this movie, starting with the possibility of a
volcano forming in the middle of Los Angeles. Firstly, since the edge of California is
located near the rim of the Pacific plate, the public may believe that it is likely for a
volcano to form; the geologist expert Amy Barnes explains that magma can rise up
through new faults created by earthquakes. According to the United States Geological
survey website, earthquakes higher than 6 on the Richter scale can cause pressure on
magma reservoirs, causing volcanic eruptions. 1 The likelihood of a magma reservoir
forming beneath LA, however, is slim. The only volcanic area in California is found in
the Cascades range, where there have been seven eruptions in the last 200 years. 2 The
development of this volcanic range is through the subduction of the Juan de Fuca plate
beneath the North American plate. 3
        Barnes also made the comparison between the nascent “Mount Wilshire” to
Paricutin, the Mexican volcano that had formed suddenly in 1943. The Paricutin
volcanic activity lasted much longer, however. Mount Wilshire appeared controlled after
the initial lava flow, and LA seemed to be safe from the volcano, but in actuality,
volcanic ash can fall so thick and heavy as to cover up entire towns. The volcanic
activity by Paricutin, in fact, lasted for 9 years. 4
        Safety issues were also greatly misrepresented in Volcano. For instance, lava is
measured to be about 1150 degrees Centigrade. So even with protective gear on,
firefighters working next to lava flows is actually very dangerous because of the intense
heat. Plus, the gases that lava can emit (such as sulfur and carbon dioxide) can injure
people’s lungs. The ash fall from the volcanic eruption can also be harmful to bare skin;
thus, the people in the immediate area within Mount Wilshire could have gotten burned
and have had respiratory problems. The reach of the ash around the eruption can spread
for miles as well; thus, the whole city should have been covered with ash, not just one
part of it. The proper precautions to deal with falling tephra is to wear long sleeved shirts
and pants with gloves, goggles for eyes, and a mask over the mouth and nose. 5 Also, the
safety precautions taken by both Barnes and Rachel were not sufficient. For instance, if a
geologist were to explore a possible volcanic vent, she would not straddle said vent
during her investigation. In fact, a whole volcanic team would have been assembled
with, according to the USGS website, “experts in several scientific disciplines who can
interpret data coming back from the field, a spokesperson to communicate warnings and
other information to public officials and the media, and a scientist-in-charge, or ‘driver,’
who assumes overall responsibility for team performance.” 6
        In one of the major events of the film, firefighters manage to stop a lava flow by
blocking off the flow, then pouring thousands of galleons of water over it; the idea was
inspired by the methods people used to “stop the lava flows in Iceland,” Barnes notes.
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True, on January 23, 1973, there was an eruption in Heimaey, Iceland, whose lava flow
was stopped by pouring excessive amounts of seawater on the flow. But according to the
USGS report Man against Volcano: The Eruption on Heimaey, Vestmannaeyjar, Iceland,
a simple set of fire hoses can not stop the flow. The project was enacted 15 days after the
start of the eruption, on February 3, using initially the entirely city’s water supply, then
several pumps loaned from the United States to pump seawater straight onto the flow. As
the watering was going on, they also bulldozed up the ground to form trenches for the
lava to flow into. The cooling program lasted until July 10, 1973, as more and more
seawater was used upon the flow – about 1.3 cubic yards per second on some parts of the
flow. In all, over 19 miles of piping and 43 pumps were used in order to cool down the
flow; over 8 million cubic yards of seawater was used in this project to cool 5 million
cubic yards of lava into solid rock, and at its most intense, 75 men worked around the
clock to cool down the flow.7 In comparison, a few dozen LA firefighters and their
trucks would not have had enough water on hand to stop a lava flow in a couple of hours,
even the much smaller features in the movie. Most of the water would have gone up in
steam; it would have taken thousands more galleons of water to cool down basalt lava
into solidification.
        As a result from these exaggerations and misrepresentations of volcanoes in the
film, the general public will have had nothing more than an unrealistic, stereotypical
impression of the subject. As Hollywood tries to sensationalize and simply the geology
in this film, people will end up believing that all volcanoes are the same, fiery, hot
images that they see in Hawaii or Mount St. Helens; they wouldn’t know the dramatic
differences between each type of volcanic eruption. Moreover, this can only promote
unsafe reactions to an actual eruption; that the public can go out into ash fall unharmed or
that they would not be affected by the intense heat or gas by standing beside lava flows.
The only advantage that this movie has is by showing a film about volcanism, people
would become more interested in the topic and research into it themselves, discovering
the truth.

                                        Footnotes


        1. U.S. Geological Survey, “Man against Volcano: The Eruption on Heimaey,
Vestmannaeyjar, Iceland,” USGS, 10 October 2001,
<http://volcanoes.usgs.gov/Products/FAQs/FAQ_EQ+Volc.html> (25 November 2004).

        2. Cascade Volcano Observatory, “Who’s Keeping Watch Over the Cascade
Volcanoes?” CVO Website, 31 May 2000,
<http://vulcan.wr.usgs.gov/Volcanoes/Cascades/Publications/OFR97-125/OFR97-
125.html> (25 November 2004).

        3. U.S. Geological Survey, “DESCRIPTION: Juan de Fuca Volcanics,” CVO
Wedsite, 26 July 2000,
<http://vulcan.wr.usgs.gov/Volcanoes/JuanDeFucaRidge/description_juan_de_fuca.htm>
( 25 November 2004).
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        4. San Diego University, “The Eruption of Paricutin (1943-1952),” How
Volcanoes Work, 25 October 2004,
<http://www.geology.sdsu.edu/how_volcanoes_work/> (26 November 2004).

        5. Seattle Red Cross, “Volcano Safety,” Seattle Red Cross, 10 July 2003,
<http://www.seattleredcross.org/disaster/safety/VOLCANO.HTM> (26 November
2004).

        6. U.S. Geographical Survey, “FAQs about studying and working on
Volcanoes,” USGS, 10 October 2001,
<http://volcanoes.usgs.gov/Products/FAQs/FAQStudying.html> (25 November 2004).

        7. U.S. Geological Survey, “Man against Volcano: The Eruption on Heimaey,
Vestmannaeyjar, Iceland,” USGS, 25 January 2000,
<http://pubs.usgs.gov/gip/heimaey/heimaey.pdf> (26 November 2004)

				
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