0523CTTGreenTuffDrape-(2)-lores University of Leicester (UK) volcanologist Rebecca Williams stands in front of a remarkable volcanic deposit on Pantelleria island. Credit: Mike Branney/University of Leicester

What’s on your to-do list?

My list of fun (and not-so-fun) tasks includes nailing down a destination for a late-summer getaway.

I’ve got some potentials and a few actual possibilities, but my much-larger collection of “only in my dreams” tropical tanning locales, historical hotspots, and seaside settings just might have to include one tiny, star-studded island in the midst of the Mediterranean.

Nestled between Sicily and Tunisia, Pantelleria has had its share of glamorous guests—Sharon Stone, Sting, Julia Roberts, and the ultimate material (no, not our kind of materials) girl, Madonna, among them.

Despite an all-star roster of famous folks, the 32-square-mile island is far from well-known. Or, at least, was. Thanks to a “ground-breaking” study of volcanic activity on the isle by a team at the University of Leicester (UK), mostly private Pantelleria is being thrust into the international scientific spotlight.

The findings, published in Geology late last year, reveal that 45,000 years ago, an extra-hot layer of emerald glass covered every last inch of the island.

“A ground-hugging cloud of intensely hot gases and volcanic dust spread radially out from the erupting volcano in all directions,” says volcanologist Mike Branney in a Leicester press release. “Incandescent rock fragments suspended in the all-enveloping volcanic cloud were so hot, molten and sticky that they simply fused to the landscape forming a layer of glass, over hills and valleys alike. The hot glass then actually started flowing down all the slopes rather like sticky lava. ‘Ground zero’ in this case was the entire island—nothing would have survived— nature had sterilized and completely enamelled the island.”


The spectacular sea-cliffs of Pantelleria. Credit: Mike Branney/University of Leicester

And though present-day Pantelleria has been repopulated and is green with vegetation, according to Branney, “even as you approach it by ferry you can see the green layer of glass covering everything—even sea cliffs look like they’ve been draped in candle wax. Exactly how this happened has only recently come to light.”

To uncover the island’s heated past, Branney, fellow volcanologist Rebecca Williams, and the balance of the Leicester team used the varying chemistry of glass to painstakingly plot out how the glass formed first in areas closest to the ground and spread to and above the hills, where it eventually (and “remarkably”) retreated “so that, by the end of the eruption, only lower ground, close to the volcano continued to be immersed by it.”

Equally interesting, this eruptive incident wasn’t Pantelleria’s only one—at least five others of “similar type” have devastated the island.

“The remarkable volcanic activity on the island was not just a one-off. And as the volcano continues to steam away quite safely, it seems reasonable that in thousands of years time, it may once again erupt with devastating effect,” says Branney.

Regardless, the Leicester scientists are hopeful that Pantelleria’s two-steps forward, three-steps back behavior might provide insights into similar and larger volcanic eruptions that occur across the globe, particularly, point out researchers, in the Pacific Northwest’s Yellowstone-Snake River region.

Want to see the “island of glass” on the map? Then head here.

To read about another interesting island (this one, covered in concrete), follow the link here.

The paper is “Temporal and spatial evolution of a waxing then waning catastrophic density current revealed by chemical mapping” (DOI: 10.1130/G34830.1).

Feature image: Even the waters surrounding Pantelleria, once covered in a similar-hued glass, are green. Credit: Gino Roncaglia; Flickr; CC BY 2.0