When I say that word ‘gas’ what do you think of? Probably the gasoline you put in your car? The gas I’m talking about is toxic gas seeping out of the ground. We went on a hike up Nea Kameni yesterday and I could smell rotten eggs with every breath I took from the gases and in parts of the island I could see the gas seeping out of the ground, trying with all its might to poison you.
In Santorini, the island in the center of the caldera, Nea Kameni, is the newest volcano. The Kameni fault line running through the center of the Santorini volcanic complex acts as a path for magma from the gigantic chamber beneath it. Like a glacier where you only see a fraction of the whole because most of it is under the surface. Nea Kameni is not currently erupting, but it does show constant signs of volcanic activity. Among these signs are earthquakes, ground deformation, and the release of volcanic gases.
There are a total of seven common volcanic toxic gases at Nea Kameni. The gases are broken into two groups: magmatic and non-magmatic. Magmatic gases are released…Non-magmatic gases originate from…The magmatic gases are sulfur dioxide (SO2), carbon dioxide (CO2), and helium (He); the non-magmatic gases are hydrogen sulfide (H2S), hydrogen (H2), carbon (CO), and methane (CO4). These gases in small amounts don’t cause problems, but in large amounts will have a deadly effect. If released in an eruption they can kill everything in the vicinity.(Fig.1)
In January of 2011, Santorini entered into a crisis period where new magma began to invade the chamber below Nea Kameni. The invasion of magma causes ground deformation and a decrease in pressure on the magma chamber allowing for more gases to escape. Scientists were able to tell that the volcano was in a state of crisis because there were earthquakes, rising elevation of the caldera floor, and increased CO2 release. The earthquakes are recorded by seismographs, the elevation change by GPS monitors, and the increase of gases by the CO2 Flux monitoring station; all of these are continuously monitored on Nea Kameni. Each of these effects of a rising magma chamber indicates signs of another potential volcanic eruption. However, the crisis period ended in May of 2012 without any significant volcanic eruption (to the disappointment of the geologist that took us on the tour of Nea Kameni, George?)(Fig.3)
Sulfur gases are easy to detect; they have a strong rotten egg smell to them and a yellowish color. On the other hand carbon dioxide or carbon monoxide have no color or odor and can kill a person without warning (in high concentrations). At the top of Nea Kameni there is a device called the CO2 Flux monitoring station. Every ten minutes it measures the amount of toxic CO2 coming from the ground, testing whether or not the air is still safe to breath.(Fig.3)
As long as the CO2 levels remain constant there is nothing to fear but if the levels start rising again a volcanic eruption could be on its way and depending on how high the gases got Nea Kameni would have to be shut down to tourists and locals. If that happens the Greek economy will take a hit because 30,000 tourists travel to Nea Kameni each year. Luckily the stations that are in place to record data will allow scientists to measure the level of danger the volcano is at. The gases will let us know when it’s no longer safe to be around the volcano, its amazing to think that a little gas could cause so many problems and could be so dangerous. Mother nature sure has some interesting was of getting back at us doesn’t she!?