This week, the class took a 6 hour trip around the archipelago to hike the still active Nea Kameni volcano and observe the caldera rim up close. Also known as “Boat Day”, it was the climax of our 3 week visit to Santorini. I had never been on a small boat before, therefore I had no idea of how to move around the very turbulent vessel, nor whether I’m prone to sea sickness or not. Thankfully I gained my sea legs and enjoyed the excursion like it was an amusement park ride. The way the boat swayed under my feet and the balance I had to struggle to find reminded me of being in an earthquake.
When Lisa told me about this opportunity to study volcanism in Santorini on the first day of class, I knew I had to go. My mother would have been furious if I passed it up. Being one of the most beautiful islands on the planet didn’t deter me, either!
I’m originally from Japan, famously known for its violent seismic activity. It’s one of the reasons why I decided to study civil engineering at NAU; it literally hits close to home. An enormous quake of magnitude 9.0 hit the east coast of Japan in 2011, and although my family and friends were safe, I still shudder from the thought of the destruction it caused to the place I call home. Most earthquakes are caused by movement of tectonic plates that cause friction between them. When enough strain builds up between the two plates, they slip, sending massive amounts of energy to the surface known as earthquakes.
Volcanoes are directly related to earthquakes because they often form on these tectonic plate boundaries. As magma rises to the surface of the earth, it finds the easiest path with least resistance, and a crack in the earth (plate boundaries) is most convenient. The movement of magma underground causes tremors in the surface.
Santorini lies on the boundary between the African plate and the Eurasian plate. The African plate is being forced underneath, or subducting, as it moves north under the Eurasian plate. These subduction zones happen to cause the largest earthquakes and the most destruction. (Japan lies on one as well).
Because of the vivacious tectonic and volcanic activity, Santorini is no stranger to destructive earthquakes. While visiting the ancient city of Akrotiri last week, I saw one of the most famous staircases in the world. The photo to the right is a staircase located in the center of Akrotiri. The marble steps have been completely broken in half by shearing. This was the cause of violent lateral shaking before the catastrophic eruption, and the Minoans probably took it as a sign to leave the city.
Fast forward 3600 years to January 2011. Santorini experienced a crisis period where small earthquakes struck the islands at an alarming rate and fear of another eruption arose. At the height of the 17 month period, we learned that there were approximately 50 low magnitude (less than 3.5, so not too bad) tremors a day! Luckily, seismic activity ceased in May 2012 and life returned to normal without any eruptions or damage.
There are 2 major faults that cut across the archipelago. The Columbos line, which affects the northern part of the island, and the Kameni line which intersects Nea Kameni and the main cities of Thera, right underneath out feet. The concentration of earthquakes near this fault suggests magma is rising closer to the surface.
Over the course of 3 weeks, I have felt absolutely no quakes. I’m actually a bit disappointed, because I would have loved to experience the energy of this fierce island. From the crisis period to the Minoan eruption to the creation of the islands themselves, seismic and tectonic activity is an inherent presence.
Walking over Nea Kameni was surreal. It is such a small, calm island now, but the thought of it erupting and changing the the surrounding environment forever makes me realize how small we are. No matter how hard we try, we will never make as big of an impact as the earth that convulses under us. Only 3 days remain on this trip, and I might just “lose” my passport because I can’t stand the thought of leaving this stunning island.
Thanks for the love, friends and memories, Santorini. Until next time.