The wide sandy beach looked calming from a distance. It stretched far out into the appearance of a seashore. But appearances can be deceiving. Edging closer, the sand seemed to be way too grainy, much more so than the usual fine sandy beaches I was used to back home.
“Patagonian sand must be more granular than American sand,” I thought out loud. My Argentinian friend stared for a moment.
“This isn’t sand.”
“No? Sure looks like sand. Just gritty.”
“It’s ash. Here, take a closer look.”
He tosses what appears to be a large pebble in my direction. I reach out to grab it but end up batting it away because its weight is less than I anticipated. In fact, it has hardly any weight at all.
Pumice? Wait, I remember this from my geology classes. Pumice is what happens when super-hot, highly pressurized rock is violently ejected from a volcano. The depressurization creates bubbles (in technical terms, it lowers the solubility of gases like water and carbon dioxide dissolved in the lava; these gases then escape), which results in a “stone” laced with holes and air.
There were stones of pumice mixed in with the finer – but still grainy – ash that made up the beach, which had appeared only after a terrific volcanic eruption from neighboring Chile, the border being only a few kilometers from here. The ocean, of course, wasn’t an ocean either – it was a huge lake in Bariloche, northern Patagonia. The beach was at least 10-20 centimeters thick and had covered what had previously been a grassy area next to the lake. Rivulets of water spurted out from now-underground (or under-ash) springs that once ran directly overground to the lake. Now, these rivulets carried a film of ash and pumice.
This was just one of the many surprises I experienced during my recent travels to Patagonia. More can be found on my Science Traveler website.
And yes, there is a story behind the crutches. More on that later.
David J. Kent is a science traveler and the author of Lincoln: The Man Who Saved America, in Barnes and Noble stores now. His previous books include Tesla: The Wizard of Electricity (2013) and Edison: The Inventor of the Modern World (2016) and two e-books: Nikola Tesla: Renewable Energy Ahead of Its Time and Abraham Lincoln and Nikola Tesla: Connected by Fate.