Saturday, July 16, 2005

The Land of Fire and Ice (and Steam and Salt and Rock. . .)

In many parts of Reykjavik, including where the apartment where I was staying, the hot water smells strongly of sulfur. (Which, apparently, is what rotten eggs smells like.) The water is plentiful and hot: it either directly or indirectly heats the homes, fills the swimming pools, powers the greenhouses that grow the bananas and the pineapples, and generates a significant portion of the country's electricity.

Iceland sits on a rift between the North American and Eurasian plates*, which are moving away from each other at 2 cm per year. So it's essentially the result of millions of years of volcanic build up as magma erupted out of the widening gap to create the island. The magma still courses and oozes in cracks and faults and calderas below the surface, occasionally still erupting. Water from the glaciers and precipitation that drips down into subterranean cavities gets heated by all that molten rock and gas, getting as hot as 350° Celsius (662° Fahrenheit) two kilometers below the surface.

Pumping the water upto the surface, it can be used to generate electricity directly or heat cold fresh water for bathing, drinking and mostly space heating. These geothermal waters usually have relatively large amounts of hydrogen sulfide dissolved in them, and at the Nesjavellir power plant, in the mountains above Reykjavik, we foreigners were shocked to learn that the Icelanders actually inject some hydrogen sulfide into the newly heated freshwater, mainly to counteract the corrosive properties of high dissolved oxygen content, but also to maintain the smell! From University of Rochester's District Energy site: "It is free of dissolved oxygen, and contains 0.5-2.0 PPM of H2S. The remaining H2S gas reacts against any oxygen absorption in accumulators and ensures that the "pleasant smell", which the users of geothermal water in Iceland have become accustomed to, is retained. "(emphasis mine.) On the trip lots of people insisted that while the water smelled bad to us foreigners, it was very good for our skin. Seeing how youthful older Icelanders look, I wondered if there was something to that theory. It's an idea that takes some getting used to--my second "night" in Iceland I even had a nightmare about sulfuric acid.

Topping off a surreal trip was our stop at the Blue Lagoon at Keflavik, a popular detour to the airport. The Svartsengi powerplant near Keflavik pumps hot sea water out of the ground, and its high salt and mineral content gives it a brilliant blue color and, apparently, skin-healilng properties. When this super hot water is done generating electricity and heating fresh water, it's still plenty warm, and is pooled into the manmade Blue Lagoon spa. (This site claims that it was originally a mistake and highlights the adventurous culture: "The residents of the area did not fail to notice the unnaturally blue lake that formed near the power plant. The bolder of the curious decided to check it out for themselves. After bathing in the warm blue lake for a couple days the Icelanders noticed that the water had curing properties." ) Wading towards my friends in a hot foggy blue pool, with lava beneath my feet, white salt plastered on my face, and rain drops fallng on my head has been one of the odder moments of my life. Here are some photos from the official site.

So is there anything to these rumors of dermatological goodness? Stay tuned.

*I was deeply amused by the fact that I live near the opposite edge of the North American plate, which is slip-grinding along the Pacific plate. Any geophysicists know if the drifting motion of the northeastern edge of the plate is at all correlated with the northern slipping motion here on the San Andreas? I'm sort of visualizing a slight clockwise rotation, but I have no idea how much of a rigid body these plates are.