BUFFALO, N.Y. – Tracking how far volcanic debris flies
during an eruption, even a small, simulated blast filmed by
powerful cameras, is not easy.
It appears, though, that an international research team led by
University at Buffalo volcanologist Greg Valentine has found a way
- but only after visiting a sporting goods store.
“I got a laugh from the guy at Dick’s when I walked
in to buy 150 ping pong balls,” said Alison Graettinger, a
postdoctoral associate at UB who helped facilitate the 12 simulated
eruptions last month in Ashford, roughly 50 miles south of Buffalo.
The team also used tennis balls to trace where the mock debris
travelled after each blast.
A video of one of the explosions is available below.
The experiments were designed to increase our understanding of
what happens during volcanic eruptions, one of Earth’s most
powerful and mysterious natural occurrences. Researchers are still
analyzing the results but Valentine, PhD, geology professor and
director of UB’s Center of Geohazards Studies, said the tests
are a rarity for a field that relies heavily on computer
He expects them to produce a first-of-its-kind dataset that will
yield results that garner worldwide attention and, ultimately,
yield data that will help safety officials better prepare for and
respond to volcanic eruptions.
Working on land owned by Cheektowaga-based Calspan Corp., the
research team, which consisted of 17 scientists and nine students
from five countries, dug two trenches – one 30 inches deep,
the other 45 inches deep. They filled the trenches with different
layers of gravel and sand to measure how deep the blast’s
impacts would be.
On the test day, researchers hammered into the trench creating
12 small holes 18 inches deep. They placed an explosive about as
powerful as a firecracker into each hole and covered the hole with
The researchers then set ping pong balls and tennis balls on the
surface above the explosives. Graettinger had previously injected
mixed limestone sand into the ping pong balls to create three
weight classes distinguished by white, orange and red markings. The
42 tennis balls were of uniform weight.
Researchers then detonated the explosives, which buried some
ping pong balls in the impact crater and sent others as far as 100
feet into the woods. In addition to measuring where the ping pong
balls and tennis balls travelled, they monitored each blast with
high-speed cameras, infrasound microphones, seismometers and other
high tech equipment.
The researchers collected the same type of information they
would during an actual volcanic eruption. The idea, Valentine said,
is to use the data to determine the energy of each blast.
Controlled experiments like those at Ashford can provide clues
into what causes volcanoes to act the way they do. For example,
many volcanoes erupt repeatedly from the same crater, yet few
experiments have been done to examine how the pre-existing craters
affect the later eruptions.