When La Palma erupted in 2021, it was the first time in 50 years for the Spanish island. This eruption was a destructive one, entombing thousands of buildings and thousands of acres of farmland. While hazardous, this eruption was a great opportunity for scientists and researchers. They studied the eruption and the materials ejected from it to increase understanding of the underground caches of magma, seismic activity, and eruptive processes.
One of the most useful materials studied by the researchers are crystals. These crystals form when lava quickly cools when exposed to air and contain the chemical materials from the magmatic source below. This allows them to capture a snapshot of the Earth’s interior that couldn’t be seen any other way. By examining the crystals, researchers can track the eruption in real time and forecast the kind of eruption and the characteristics of the magma.
On La Palma, the lava was mostly ‘A’ā, meaning that it did not produce a typical cone-shaped mountain, but moved like rubbly serpents of melted stone. These flows are filled with natural glass formed from the quick cooling. When the lava advanced, it created a sound like broken glass, due to the cracks and snaps from the temperature change.
For the 2021 eruption, experts used various methods to sample the lava. Some used shovels or pincer-like metal claws, others used banana tree poles designed for picking the fruit. Obtaining the samples involved dodging exploding pieces of lava and ash. Then, the samples were extinguished quickly in a steel bucket of water to preserve their subterranean chemistry.
The crystals inside the magma can be used like barometers, telling researchers the pressures the lava was once subjected to, which then indicates the depths of the volcano’s magmatic kitchens. Inside the crystals also lies information about the ingredients used to cook up the magma.
Now, real-time monitoring of volcanoes is made possible to forecast future eruptions. Besides listening to seismic rumblings, studying these crystals can provide a more comprehensive understanding of the eruptive processes to allow emergency responders to take the appropriate actions.
Overall, the 2021 La Palma eruption, while dangerous, provided valuable insight into volcanic activity. It demonstrated to us the great power of nature as well as the knowledge that can come from studying crystals and other debris created by an eruption