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Interesting Questions, Facts and Information
- There are a total of 20 general entries.
Special Topics
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 Interesting Questions, Facts, and Information
 Volcanoes
| When we think of the consequences of volcanic eruptions, we tend to think of whole swatches of land burned beyond recognition, people injured or left homeless, and if we're creative we think of things like climate change and so on. But here is far stranger tale.
The 1815 eruption of Tambora in Indonesia was the largest in recorded history. The following year, 1816, was called "the year without summer." A group of friends went on vacation in Switzerland that summer, but it was so cold and nasty that they spent almost their entire holiday indoors. They decided to pass the time with a scary-story writing contest. The contest was won by Mary Shelley, who decided to call her creation... I seem to have forgotten. What was it? | Strange Facts about Volcanoes
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Frankenstein. I'll bet you didn't know that Frankenstein wouldn't have been written if it wasn't for a major volcanic eruption! I hope this quiz has given you an appreciation for the finer points of volcanoes-- let's just hope there's no major volcanic eruption any time soon!
| The Laki eruption produced climate change in places as far away as the fledgling United States of America. Which American founding father was the first person to make the connection between volcanism and climate change? | Strange Facts about Volcanoes
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Benjamin Franklin. Franklin's scientific prowess extended beyond the lightning-and-kite experiment that everyone hears about. Franklin thought "smoke might be spread by various winds, over the northern part of the world," causing the massive crop failure in the US of A. Right on. To elaborate further, volcanos spew stuff above the troposphere, where weather occurs, and into the stratosphere. While the stuff in the troposphere is washed out by rain relatively quickly, the stuff that reaches the stratosphere can persist for years and years.
| The 1783 eruption of Laki on Iceland was a huge catastrophe. 22 separate volcanos erupted on a crack 15 miles long, piled up lava 60 feet high in places, and poured an enormous amount of toxic gasses into the atmosphere. Over 9,000 people died on Iceland alone. What was the single largest cause of death? | Strange Facts about Volcanoes
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Starvation. While the toxic gasses did not kill off the people, they did kill off the livestock that the people in Iceland relied upon for food. So, a huge percentage of the population starved to death. In other regions, like France and Egypt, where most of the population lived off of subsistence agriculture, large numbers of people starved to death as well.
| About 65 million years ago, a series of massive, massive volcanic eruptions spilled about 12,275 cubic miles (512,000 cubic km) of basaltic lava over west-central India. That is truly a lotta lava. Today, the formation is known as the Deccan Traps. This major geologic event took place suspiciously near to the famous mass extinction of which animal group? | Strange Facts about Volcanoes
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Dinosaurs . Before anyone discovered the Chicxulub crater, the formation of the Deccan traps was the main theory to explain the mass extinctions at the end of the Cretaceous. After all, even much smaller volcanic eruptions, like Krakatoa, can cause substantial climate change. Now that some scientists are questioning the date of the impact crater, the volcanic eruption hypothesis may experience a renaissance. Or not. Wait and see!
| Different volcanos produce lava of different viscosities. This is the main reason some volcanos erupt explosively, and some just spread runny lava over a large area. To give you an idea of how the difference in viscosities of different types of magma, consider the following experiment. You have two swimming pools, one filled with basaltic lava (think Hawaii), and one filled with rhyolitic lava (think Mount St. Helens). You drop a steel ball in the basaltic lava. It takes about eight hours to sink to the bottom. You drop a steel ball in the rhyolitic lava. About how long does it take to sink to the bottom this time? | Strange Facts about Volcanoes
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900 years. Thanks to my geology prof. for this one. This was possibly the coolest (hottest?) thing out of the many cool (hot?) things I learned in his class! The reason for the difference in viscosity is the difference in composition of the magma. Rhyolitic magma has a high percentage of silica, which tends to bond with itself and increase the viscosity. Rhyolitic magma also has a higher percentage of dissolved gasses, which power the explosions. Ker-POW!
| The "Ring of Fire" is a region of extensive volcanic activity along the edges of the Pacific Ocean. It contains the largest number of active volcanos in the world. What other geologic event is creating this massive amount of volcanism? | Strange Facts about Volcanoes
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The Pacific Plate subducting. As the Pacific plate subducts under the neighboring plates consisting of continental crust, the continental crust heats up and eventually melts. The magma eventually shows up at the crust as volcanos. Interestingly enough, the subducting oceanic crust does not heat up significantly, because the continental crust acts as a heat sink. This results in a rare high-pressure, low-temperature metamorphism that can form a rock called "blueschist."
| Luckily, nowadays things are much more restrained. Volcanism produces about 4.1 cubic kilometers of lava worldwide each year. Where does most of this lava come from, by far? | Strange Facts about Volcanoes
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Midocean ridges. Volcanism at mid-Atlantic ridges creates about 3 cubic kilometers of lava annually. Since it's at the bottom of the ocean, we're not usually aware of it. Here's how the process works. Tectonic plates pull apart at midocean ridges. This causes the mantle to upwell at that point, and the decreasing pressure causes some components of the mantle to melt. The magma emerges at that place, making a volcano. Since the magma comes from partial melting of the mantle, it is basaltic in composition. That all sounds very impressive, doesn't it?
| This quiz has been about supervolcanoes, a term that came about in the year 2000. Who originally coined this term? | Supervolcanoes
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The British Broadcasting Corporation. The BBC (British Broadcasting Corporation) coined the term for their science program 'Horizon'.
| There is a catastrophe theory linked to an eruption of a supervolcano. This theory, though widely debated, says that there was a dramatic loss of human life because of the eruption and everyone is genetically descended from the mere few thousands who managed to survive this event. Which supervolcano erupted? | Supervolcanoes
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Lake Toba. As well, the eruption caused the average temperature of the earth to drop by 3 - 4 degrees Celsius (up to 15 degrees Celsius in more northern regions). This theory is called the Toba Catastrophe Theory.
| Supervolcanic areas, such as Yellowstone, are under immense pressure. Scientifically speaking, is it possible to alleviate some of this pressure and thus lower the risk of an eruption? | Supervolcanoes
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No. To alliviate such pressure, the volcano would have to be drilled into. This would not only be extremely dangerous and expensive but it wouldn't work. The hole that's drilled would only be filled in by the minerals in the volcano. As well, it would be very difficult to drill through magma.
| Yellowstone erupts once about every 660,000 to 800,000 years. It's last eruption was around 640,000 years ago. What type of eruption do scientists believe is likely to happen next time it erupts? | Supervolcanoes
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Lava flow eruption. Scientists believe that the odds of a catastrophic eruption are extremely rare in the coming thousands of years. The chance of a smaller eruption is also rare (there are about 100 every million years), however, more probable than a catastrophic, caldera-forming one.
| Only once or twice in every million years is there a supervolcanic eruption big enough to create a caldera. Which supervolcano, located in Sumatra, Indonesia, had this type of eruption 75,000 years ago? | Supervolcanoes
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Lake Toba. Toba was one of the world's largest known eruptions, ejecting over 2,500 cubic kilometers of magma. The caldera that was created is 30 by 100 kilometers and is located under a lake.
| What is created after a catastrophic eruption of a supervolcano? | Supervolcanoes
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Caldera. Volcanoes are formed when magma (liquid rock from under the earth's surface) erupts from the mountain and eventually cools and solidifies on the mountain itself. However, there is so much pressure during a catastrophic supervolcanic eruption that too much magma is ejected to form a mountain. The land then collapses and forms a caldera (a cauldron-like shape).
| A supervolcano is a type of volcano. But what is it about supervolcanoes that make them so 'super'? | Supervolcanoes
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Their eruptions are large and catastrophic. There isn't a scientific definition for a supervolcano, however, the generally accepted definition is a volcano that ejects over 1,000 cubic kilometers of magma. To put it in perspective, the 1980 eruption of Mount St. Helens was only 1 cubic kilometer.
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