Since nearly 50 years, cinema has misrepresented volcanoes. These burning mountains are used in many disaster movies as an ominous symbol of power and danger. The physics of these burning mountains is rarely discussed, and they are only used to create smoke and lava in movies.
Some of these flaws relate to the effects of volcanoes on the environment and life, for example, the density, speed, and heat of magma. These concepts can be ignored by fantasy films like Lord of the Rings, (2001-2003), as well as disaster movies such Dante’s Peak or Volcano. Even though disaster films are centered around volcanoes, they have some of the worst flaws.
It is a common misconception that volcanoes are large mountains that emit giant clouds and lava. Volcanoes can’t do both. They either explode with ash (also called pyroclastic storms) or they spew molten rocks. Contrary popular belief, the clouds can be more dangerous than the lava. The magma’s consistency is the reason. The amount or silicon determines the ability of magma to either flow or solidify. When magma has a high silicon content, it can block gases, which causes pressure to increase. When stratovolcanoes explode, they do so with incredible speed and force. But there is no lava present, because the magma has been hardening, and thus preventing gases from escaping. Shield volcanic eruptions, on the other hand, send molten rocks into the surrounding environment. Because of their low silicon content, shield volcanoes produce lava flowing from flat short hills.
The characteristics of the volcano are then generalized to make it appear larger and more destructive. It is particularly evident in Dante’s Peak. The 110 minutes of the film show everything that goes wrong with a volcano, such as earthquakes. Lava floods are criticized because they do not create a dramatic and convincing climax. In a movie scene, the protagonists go to a mountain cabin with their kids to save their grandma. The magma erupts from the back wall of the cabin as they leave. Within seconds, the entire living room is flooded. The peak of the stratovolcano should not have any magma flowing, much less lava moving at high speed.
Mount Doom is another example of a stereotypical event in the Lord of the Rings series. It combines all the tropes of volcanic activity into one. Return of the King’s final scene incorrectly depicts the density of the lava. Gollum drops the One Ring into the lava after the final battle of Frodo versus the malignant Gollum. Gollum falls into the molten rocks in just six seconds. The ring, however, floats for an entire minute on top of the crust. A person would have to be more dense than a metal in order to sink under a pool lava. In reality Gollum’s ring would have been the first to sink, as it was just burning.
Volcano from Mick Jackson, a disaster film, is a great example of magma and living organisms interacting. The concept of a lava hotspot beneath Los Angeles is humorous, but Olber’s attempt to rescue train passengers who are about to be engulfed with molten stone is inaccurate. The lava is already under the car and it’s impossible to jump. Olber decides on a self-sacrifice by launching the passenger out of the lava, and melting into it as he does so. Human bodies can burn, not melt. A body cannot change viscosity to a level of less than a foot in lava. Olber should’ve been feeling the heat even when not in contact.
These stereotypes of heat and volcanoes in cinema are not only repetitive, but also nonsensical. The lava is too dense to swallow anything, and the effects of different volcanoes are not limited to smoke clouds and lava flows. The visual/simulation department should be given more attention by producers and directors.