I arrived in Tennessee just a few days ago, ready to take over the care of my granddaughter while my daughter and her husband took a trip to Germany. However, Iceland and its explosive ways have altered the plan somewhat.
Ironically, I used to teach elementary students about plate tectonics with a slide show called, “I feel the Earth Move under My Feet”. In it, I explained how cool it was that, in Iceland, you could see the “sea floor spread” of the North Atlantic Ridge happening right before your eyes. Well, at the moment, with their flight canceled, it doesn’t seem quite so cool! If only the proverbial dust would settle, they may be able to try again later next week.
But meanwhile, it leads us into a discussion of plate tectonics, which really is an interesting and easy to understand concept. One worth pursuing as it seems to be in the headlines every other week! In a nutshell, and you probably know this already, the earth’s crust is broken into several major plates and many minor ones, and they can move in various ways. Understanding their movements is a good way to understand many of the more dynamic things we see happening on and in the earth.
For instance, two equal size plates crash together and you have mountains rising, AKA the Himalayas which are still ascending to greater heights as we speak. Two plates grind past each other in opposite directions and the results are earthquakes, when one side finally makes the jump, sending shock waves through the ground. This is what has been forecast for California for so long, but seems to be happening everywhere else. Two unequal plates meet together and the heavier plate sinks beneath the lighter one (subduction). The resulting melting rocks find a way to come exploding back out in the form of volcanoes, as we see in the Ring of Fire around the Pacific plate.
In Iceland you are seeing the opposite of subduction. Instead of one plate plunging beneath another, two plates are being pulled apart and new crust is forming. This generally happens at the bottom of the ocean floor and it is referred to as the Mid-Atlantic Ridge. Due to the great water pressure above it, this magma doesn’t explode but instead oozes out. To see it, you would have to be in a high-pressure submersible sub like “Alvin” from Woods Hole. Then you could travel down and see the smoking vents and fissures that have extreme high temperatures and entire ecosystems around them.
But if you are in Iceland you are on the one spot on the Ridge where this is happening above water. The plates are spreading, the lava is gushing, the dust is rising, and planes aren’t flying. To make it even more exciting, all of this is happening under a glacier, so you have steam shooting up hundreds of feet and glaciers melting. Yikes! And it has only happened like this 5 times since the 9th century. What were the chances it would happen the day her plane was to fly!
On the plus side, Iceland is not covered with snow and ice as it would be otherwise, the people enjoy affordable geothermal power, lots of free hot tubs, and vegetables that grow year round in hot houses powered by rising magma heat. But on the down side, you just may have to evacuate in the face of an onrushing flood of melt water, or noxious gasses or flowing magma. Maybe the Realtor forgot to mention that when you bought the property.
And for your folks worried about global warming, volcanic ash has a tendency to reflect the sunlight back into space and cools things off a bit. In 1815 Mt.Tembora erupted with so much ash in the atmosphere that there was no summer at all in Europe. Not that this is that bad. And so, tempted as I am to complain about the inconvenience, this still is a pretty amazing event, not that I expect my daughter to see it that way, if next week, the flight is canceled again. More than volcanoes will be erupting!
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