Volcanologists are an impatient bunch. Instead of waiting for volcanoes to erupt, they sometimes use explosives to simulate their own artificial eruptions. Similarly, instead of waiting for lava to pour out, they grab some rock and melt their own.
The University at Buffalo (UB) in New York State is one such research institution that brews its own vast lava batches. They’ve just started work on a new supply that will go towards both advancing the complex science of volcanology, as well as some seriously cool YouTube videos.
The recipe is relatively simple. Take a load of basaltic rock, dump it into a powerful furnace, leave it to melt for a few hours, and occasionally stir. No seasoning is required. Once the mixture is molten, it’s good to pour out, but don’t leave it to stand for too long – even lava at a ridiculous 1,370°C (2,500°F) cools down eventually.
So why are UB in such a rush to produce so much man-made lava? Well, one of the most frustratingly unanswerable questions in volcanology right now revolves around the rendezvous between water and magma, and these experiments may help to address this somewhat.
Just like a good coffee, it’s all about the pour. University at Buffalo via YouTube
Some of the most unpredictable and explosive eruptions in the world are so-called “phreatomagmatic eruptions,” those that occur when magma erupts into water. They often occur during the formation of maar volcanoes, a bizarre but commonplace volcanic depression pit that resembles small nuclear weapons testing craters.
As a ton of experiments have already shown, just pouring magma on water or ice doesn’t actually cause an explosion. Instead, the magma touching the water or ice causes the surface to suddenly boil, creating a layer of vapor. This vapor film insulates the hot lava from the rest of the water, which prevents most of it from rapidly and violently boiling.
This is known as the Leidenfrost effect, and explains why famous scenes of Hawaiian lava dripping into the Pacific Ocean – a favorite of photographers everywhere – doesn’t result in an explosion. Nevertheless, when magma erupts into overlying water or ice, there appears to be highly energetic explosions, and volcanologists aren’t entirely sure why.
These reactions, whether slow or fast, calm or explosive, are sometimes referred to as “molten fuel-coolant interactions,” or MFCIs, where the water is the coolant and the magma is the fuel. The more violent MFCIs are poorly understood, and UB hope to force their manufactured lava to mix with water in such a way that it causes an explosion.
“Previous studies have used a coffee cup-sized amount of lava,” UB geology postdoctoral researcher Alison Graettinger said in a statement. “We're doing it bigger, because there are a lot of questions about whether we'll see the same results when experiments are scaled up.”