Skaros from the sea
Skaros from the sea (Chris Crivelli)

The June 2002 edition of the newsletter carried an advertisement by the Mainland Europe Group, which invited members to spend a week studying the effects of subduction zone volcanic activity with special emphasis upon one particular island. The volcano that formed the island had erupted in what is now considered to be the second largest eruption within historical times with an estimated VEI (VEI = volcanic explosivity index) of ~7. Only Tambora in 1815 produced a bigger eruption. The volcano which was to be visited had erupted so violently that it contributed to the demise of a civilisation, deposited massive layers of pumice and other products, and caused a tsunami which devastated low lying areas over 31500 km2. It is depicted as being either a whole island strato-cone, or a smaller island strato-cone surrounded by the remains of an earlier strato-volcano. An important hub for trade, its destruction had global effects. For many OUGS members this was to be the first time of visiting a volcano whilst for others it was the first time of standing on a subduction zone volcano - known as Calliste, Thira, Thera, or Santorini. Students of S339 should at least be familiar with the island as it forms much of unit 3.

So it was that on Saturday 19th October, I and eight others met at the Olympic check-in desk at Athens airport for the flight to Santorini. Not for us the walk down a bridge to the aeroplane, but a bus ride. The look of amazement on one or two faces summed up the feelings of many when they realised that the aeroplane had two crosses stuck in front of the engines. I found it hilarious as, in my opinion, real aeroplanes only have propellers on the engines - not the jets that charge across the sky! We boarded via the rear door up an integral ladder and found our seats. For safety reasons seat backs are upright for take off and landing in all aeroplanes. In my case it was a joke - the seat auto-reclined under any pressure, remove the pressure and hey presto it went upright again. We were given the safety brief in Greek and English, both of which were unintelligible - all those earlier safety briefs now came into their own. Our aircraft took off as the sun was approaching the western horizon, and turned on to a southerly course. Those of us sat on the starboard side saw the sunset which was not remarkable.

The information that I had received said that the approach to the airport at Santorini was accompanied by a sharp turn over the rim of the caldera, followed by a steep descent and sudden hard braking on the runway. The pilot cheated - he flew straight from Athens to Santorini and landed on the runway - no aerobatics at low level. What a wimp!! We disembarked at the terminal, collected our baggage and went in search of our transport.

After a struggle we managed to get all the luggage loaded into a minibus and a car. The care hire staff drove us to their office "somewhere in Fira". After the formalities were completed we had to disembark and get our luggage into two cars. That accomplished we set off to find our accommodation. Driving in a strange place at night with road signs written in an unfamiliar text gave rise to a few interesting moments and it must be said that it is to the credit of the "Two Chris's" that we found our accommodation. Having sorted out who was sleeping where, we went in search of food. Lets just say that there were far better establishments - one in particular that would give us the "honoured guest" treatment - more anon.

Most of us were tired from travelling (one hardy soul had "slept" at Athens airport on the Friday night) and that plus the time difference of UK plus 2 hours meant that we were getting up the following morning at a time when we would normally be asleep. It also meant we had to go to bed earlier than we would normally. So ended our first day.

The following morning the two Chris's went in search of sustenance for us all and whilst they didn't bring tonnes of delicacies etc., they did bring food. They were to dig out food for us on an almost daily basis. It was whilst we were eating our breakfast that someone realised there was no sign of other people staying at our accommodation. We found out later that there was a simple answer. We nine were the sum total of guests and when we left the owners were going on their holiday to the West Indies.

After breakfast we loaded ourselves into the cars and set off to see the basement rocks of the island. We were to see the full gamut of rock types - sedimentary, metamorphic and igneous - sometimes in close proximity to each other. Chris 1 under the excellent navigational expertise of Chris 2 was to be the lead car in almost all our travels.

We eventually arrived at a location where the road went steeply up in a series of hairpin bends. Eventually we reached the summit and some of us unwound ourselves out of the cars. A gale was blowing as the wind was forced upwards by the mass of the hill. Some of us decided for various reasons not to ascend further and went in search of what geology we could find. I saw a piece of "pumice" and being a little surprised plus its colour, I picked it up. As soon as I picked up I knew that no matter what it was, it most certainly was not pumice. It was heavy, had a brown-dark green colour and was roughly oval. Examination with a hand lens showed that the holes were due to the erosion of some mineral. The sides that had not been exposed to the weather showed glassy crystals that were a pale-green or white. Olivine is a glassy pale-green in fresh crystals and can weather to a white amorphous mass. What I had was an olivine nodule, its overall colour being due to the presence of the Fe-Mg enrichment.

After we had all squeezed ourselves back into our respective cars we set of to find somewhere for lunch. Stopping in the nearby town we hunted down a decent looking Taverna. Tables were squeezed to make nine places, menus produced, drinks ordered - those of us who ordered beers were given iced glasses. The food ordered started to appear and so we dined. Once we had finished and had paid, we re-entered the cars and headed off into the capital Fira, which in common with most towns on Santorini was built on the rim of the caldera.

For a couple of hours we became tourists and Annette was told in reply to her telling a waiter what we were doing "The volcano is as dead as my grandmother" otherwise known as NIMLT - Not In My Life Time! or was he suggesting that since his grandmother was alive so was the volcano. We paused and consumed an afternoon beverage which ranged from iced tea to beer. By now the afternoon was drawing to its conclusion and we chose somewhere to sit and wait for the big orange to sink into the west. As it did we were rewarded with a spectacular sunset. We wended our way back to the cars and set off back to our accommodation, completing our journey in the dark. By mutual consent we had agreed to stay in and buy our meal from the proprietors.

We discussed many things including whether we should have had a leader who "knew the geology blindfolded". Whilst such a person does have a place, we were a group of mostly 3rd level students and many of us are expecting to graduate from 2003 to 2005. As such, WE should be able to interpret the geology as WE were due to become the latest "experts" to hit the street. We were honoured to have a member of the group to whom geology was not their forte. Every group should take at least one non-geologist into the field and encourage those of us who are "geologists" to step back and evaluate how we present our answers to their questions. Sue, I hope you were not left baffled by the answers to those questions you asked.

I for one was out of kilter - my body clock was somewhere west of Longitude 60. So we tended to retire reasonably early by British time. Greece is 2 hours ahead of London and some people can handle time changes better than others.

On Monday we went up another hill to a monastery to look at the metamorphosed sequences. The view was something - we could see the caldera rim and the deposits of the Minoan eruption where the airport was built. We were about to start the shutters clicking when someone said that there was a sign saying photography was forbidden! With the thought of the aircraft spotters and their problem in our minds we all reluctantly put our cameras away. There was a military installation nearby, hidden by trees and it is doubtful if even with high magnification that anything could be discerned that would be of use to a potential enemy. We drove to a lower level in search of some good exposures and views. It is to my mind stupid to put military establishments on top of a hill, especially where the view is incredible and then forbid photography. Our own (UK) has a lot more relaxed attitude to its establishments. In any case, its not so much the building but what is inside that has to be kept from nosy people. The Greeks are paranoid about the Turks, yet so many of the Greek islands have direct links to the Turkish mainland that it makes one wonder.

That lunchtime was memorable - we didn't buy it in so far as we bought in bulk and had a picnic. The view was good - black sand/shingle and the blue of the Aegean. After dining on bread, cheese and monkey sticks, we wandered naturally onto the beach and assumed a typical position. There were several interesting stones and slowly most of us accumulated a little pile in our arms. The beach was deserted except for nine people looking at the stones or spinning them onto the water to make them bounce a la Dam Busters and someone sunbathing. Then it was time to move on to the next exposures. Only we didn't. Someone had lost their spectacles without which they were as blind as a bat. We assembled again on the beach and formed a straight line then moved slowly along the beach towards the sun bather. As we drew closer to the sunbather there was a cry of "Found them". Which was just in time as either we were going to have one topless irate woman of ample proportions or we were going to have to go through the rubbish from lunch! Both could have had interesting results.

Each day had its own theme - where we looked and discussed the what, where, why and how. We visited a winery where you could taste different wines, which I thought was great until I realised that you had to pay to taste the wine!!! The influence of my ancestors who lived in a land where frugality was a bye word suddenly kicked in. My pockets extended and my arms shrank.

Main Town of Fira
Fira, the main town, perched on the caldera edge (Annette Kimmich)

After that we descended literally down the rim of the caldera along a road that clung to the rim. The height was accentuated when a vehicle coming up came into sight and looked like a prototype for a "Dinky toy". As we went down it was interesting to see the change from volcanic products to basement zig-zag golden schists and some limestones.

We explored the small harbour of Athinios which was also the ferry terminal. Annette, Chris 1 and myself went in search of hiring a boat with the aim of visiting the islands. We met a man who was about to leave, but kindly gave us some information about where to book, prices and mentioned the words "Discount for Students". This was getting better all the time! We had afternoon tea or coffee or beer and decided we had seen enough for the day. Eventually we piled back into the cars and headed back up the caldera rim. The cars were automatics and judging by the amount of gear changes they did its perhaps as well that they were. To get some idea of the gradient imagine a road which climbs from sea level to over 200 m as a series of steep inclines with hairpin bends and each leg being just 2 or 3 hundred metres long. I can't recall the number of inclines - but there were a lot! An aeroplane taking off had nothing on us for a "nose up."

As sunset was approaching it was agreed that we found somewhere to have our dinner where we could see the sunset. Be warned the number of places offering the "best sunset views" are numerous. We came across a taverna which we had passed on a few occasions which went by the unlikely name of Senr Zorba and served Mexican style meals - spicy hot. The staff quickly re-arranged tables so that we could sit together and we went through the preliminaries of selecting drinks and food. Slowly the sun slid towards the horizon and this sunset was looking like a good one. Meanwhile as the sun slowly sank so did the temperature and I could feel myself getting colder by the second. Not expecting to stay out I had omitted to take some warm clothing with me. I had ordered a spicy hot meal which was delicious, but did nothing to warm me up.

The highlight of the trip was to me the trip to the islands which are the new surface expression of the new volcano. These two islands - Nea Kameni and Palea Kameni are active volcanoes with Palea Kameni last erupting in 1950. It is a series of basaltic lava flows and cones which have erupted episodically since the Minoan eruption. The 1950 crater is still venting gases amongst which is sulphur dioxide which in some places is depositing sulfur crystals around the orifices. Many of the emissions from the fumaroles are hot as in they burn and it is possible to be scalded too, as some are emitting water vapour in excess of 70C.

Unfortunately some parts of the island have been defaced by morons and the inevitable spray paint and sadly some of the work appears to have been done by British visitors. One can only wonder "why?".

We stayed about an hour at Palea Kameni and once everybody was aboard we sailed to Nea Kameni where there was time for a swim and a visit to a hot spring that was emitting hot water just below the level of the sea. Then we went to the western rim of the caldera Therasia, where we were to spend two hours and the only way up from sea level to the town is either by the old ancient and proven method of putting one foot in front of the other or by hiring a donkey. We all stayed by the sea eating our lunch and just exploring. Then suddenly, it was time to leave.

When the trip was booked, we had arranged to sail on the "glass bottom" boat and this was about to be used to its full advantage. The boat sailed over the reef below Therasia, manoeuvring to give the best views. Those who were interested in seeing the reef-inhabiting fauna were disappointed by the sparse life. There was more to come - as the boat slowly manoeuvred towards the centre of the caldera the sea bed suddenly dropped away, we were now over the original pre-Minoan caldera. Those who have seen the documentary "The volcano that blew the world away" will have seen the underwater scenes where Dr Mark Davies was exploring the submerged parts of the caldera and at one point he went over the rim of the submerged caldera and said " for the first time in my life I have vertigo ". I didn't suffer from vertigo, but I do know what he meant. It was eerie to see the rim of the caldera just drop away and it is over 500 m deep!!

Our boat was aiming for Oia pronounced "O ya", which had been destroyed in 1956 by an earthquake. It has been rebuilt, but the forces that caused the destruction still exist and it is only a question of when. Like the mass of magma that is still beneath Nea Kameni, the seismic activity owes its existence to the movement of the Eurasian plate as it overrides the slow northward motion of the African plate. We stopped at Oia just long enough to let three or four people jump ashore, then we headed back towards the port of Fira.

One of the "management skills" that is taught to managers is to look at things from a different perspective. The day before we had seen the caldera rim from on high and could see many features associated with a known zone of faulting including dykes which were clearly creating an extension zone. To see this zone now from sea level was interesting as many features which had only been partly visible or even conjectured were now very visible. It would be interesting to return with a helicopter and a suitable camera to take photographs in a similar manner to aerial photographs and then be able to study them. After all it is about the only way the full extent of the caldera wall will be able to be studied closely - the only other way would be to climb or abseil at regular intervals to log the sequences.

We disembarked at almost the same spot where we had set out earlier that morning to sail around the caldera. Some opted for a four legged mode of transport and according to the brother of the owner of the donkeys Michael Schumacher and a few other formula 1 drivers had better watch out. The rest opted for a more sedate form of travel in the cable car. If it had been decided to make a race to see who would get to the top first it could not have been bettered - a dead heat was the result as we re-assembled at the top of the "donkey steps".

We were aware that our time on the island was drawing to a close and the previous evening we had dined at a taverna where we had dined on Monday - the owner, Dimitris made us very welcome on both occasions and we had agreed to dine at Dimitris's taverna again on the Friday. Arrangements had been made for those who wanted to have fish for their dinner on Friday.

Friday saw us inside the ancient town of Akrotiri which is being excavated from beneath about 30 m of Minoan pumice. Those who have done S339 will have seen the sequence in the video which shows the result of a preeruption earthquake. To me it was awe inspiring to actually see and walk along streets that had not seen the light of day for some 3500 years. It also emphasised the power of the volcano, I suspect that I was not the only one affected. However, I do think the price was expensive for what we actually saw, which was not a lot although to be fair the whole area is being excavated and studied and the last thing you need is tourists dropping their rubbish. It would be interesting to hear some archaeologist explain the presence of a chocolate bar wrapper inside a layer of pumice.

We went on to the quarry on the south side of Thera and spent some time examining the various structures. The Minoan deposits stand out from the pre-eruption deposits. The geology is incredibly complicated and yet so simple at the same time. Due to the friable nature of much of the Minoan deposits it is possible to inhale volcanic dust that is some 3500 years old and is still a killer. We tend to think that when an eruption ends everything slowly resumes its pre-eruption place and that there will not be any more deaths associated with the eruption. Cristobalite is a needle form of quartz and inhalation can cause silicosis which kills.

Then we returned to our accommodation to prepare our baggage and ourselves for dinner. We agreed a time to meet and at the due time we set off to Dimitris restaurant, where we were made extremely welcome. We selected our meal from the menu and ordered our drink. After we had finished eating we were treated to live entertainment. Dimitris produced his accordion and sang several songs in Greek to us. One had a line which went "tikka tikka tikka tak". Dimitris explained it was a love song and the tikka tikka tikka tak was supposed to be the sound of a boys heart when he met his love. Prior to the meal he had introduced us to his daughter Anna-Marie. It was her 2nd birthday and on Saturday she was having a party with her friends. We sang "Happy birthday" to her. We had enjoyed ourselves, seen some very interesting geology and now we had to leave.

The following morning saw us pushing and shoving our baggage plus ourselves into the cars. We arrived at the airport and got out of the cars. At the check in Annette produced all our tickets and then we waited. It is the travellers burden to travel in a hurry up and wait manner, especially when the journey involves aeroplanes. Eventually the whine of jet engines became audible as a jet taxied up to the terminal building. Dawn was breaking. There were three departure gates numbered 1 to 3 and at last we were instructed to board through gate 2. We left Santorini on board an Olympic Airways Boeing 737 - Biggles must have overslept. As the aircraft banked to port over the caldera I got a glimpse of the caldera wall in the vicinity of Oia and the water looked grey and uninviting. Then we were over Therasia and the aircraft straightened on its course back to Athens. A rush for breakfast and then the long wait. Our departure was subdued as first one and then another left to board their flight home. Then I was all alone and I went in search of the check-in desk for my flight back. When I arrived in Athens it was 23C and humid, now when I was preparing to leave it was still 23C and humid. I finally arrived home in pouring rain and the harbingers of a storm were making themselves known. I had enjoyed the company of the rest of the party and I hope they enjoyed mine

Was it worth it - undoubtedly yes and Annette is to be congratulated in putting the trip together. All too often we forget that before you even set foot out of your home to go on a field trip someone has had to do a lot of work to hopefully ensure that there are no hiatus's. To take people who have different levels of knowledge and investigate the geology of an area is time consuming. Annette, in my humble opinion you did the business.

Lastly, I would like to say thanks to my fellow travellers:- Annette and her husband Hans, Dave, Chris 1, Chris 2 and his wife Sue, Ann and Briarlie for their company and inspiring discussions.

By Gerard Valleley

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