30/07/2009 Greece VI: Something that doesn't belong

Another trip up into the Pindos, from sole at Loumnitsa (unfortunately blocked by a rather large landslide) up to the transitional Moho with sheared gabbros, then back down and through the Aspropotamos Complex on the way back to Grevena (to allow Dina to pick Babi up from Kalambaka).

Amphiboles of the day

29/07/2009 Greece VI: Black Mountain

Today was the first of three days with Nikos and the IGME LandRover. As a result, we were able to travel to regions of the Pindos Mountains that would otherwise be impossible. Of course, this isn't an ordinary LandRover; the vehicle is at least 15 years old, and because of this has no seatbelts in the back. The suspension was pretty good, but our heads were still more reminiscent of the Churchill dog than that of a human for most of the journey.

Most of the day was spent up Mavrovouni. We saw several faults in the fresh mantle peridotites, some of which have green and white amphiboles in them, suggesting that fluids aided faulting (I'll probably do some work on these in the next year, as the literature on exhumed mantle faults ignores fluids). At the top, we took some pretty good panoramas, and Annie almost made it up to the very top, which is a huge advance on the last three years.

After coming back down the mountain past the trekkers' shelter, we travelled to Vovousa, a beautiful village in the heart of the Pindos, and a possible village for future mapping groups - especially given the fact that the nearest mountain is basically an upside-down ophiolite (lavas, overlain by cumulates, and capped by peridotites). We finished the day with another lovely meal at Aetofolias, before returning to Grevena.

Me, working hard on Mavrovouni

28/07/2009 Greece VI: Serpentikitty

Today, we decided to continue our voyage of discovery into the ophiolitic floaters on top of the Pelagonian. Most of them happen to lie along the Via Egnatia, which makes our jaob easier. Even better is the huge number of roads in and out of villages in the area, and the fondness of the Greeks to use serpentine as road material (and for chrome and nickel).

First stop was effectively a huge hole cut into the ground, comprising massive serpentinites (from dunite and harzburgite) and wehrlites, multiply deformed, and probably about 100m thick. Near the top of the outcrop, a lateritic layer and overlying Cretaceous carbonates were cut by a NW dipping fault. Absolutely impossible in the short time we had to work out exactly what was going on - but there is no question that the last movement of the sheet was under extremely cold conditions (some of the serpentinite was brecciated and then rewelded).

Crossing the Via Egnatia, between Kalamia and Lygeri, we were in for an unexpected surprise. The site itself was interesting: roughly parallel faults bounding an exatremely sheared and folded serpentinite mass, and an extremely silicified carbonate on the east side of the road. But far more interesting was the sound we heard as we stopped the car. We were greeted by a high pitched, extremely insistent crying. Dina was the first to get out, and by the time I had joined her, she had a kitten in her arms. Extremely thin, alone and absolutely terrified, there was no way any of us could leave it to die.


We only looked at a couple more nearby sites, just off the road north of Nea Nikopolis, but in that time the kitten had eaten most of Anne's sandwich (later to also be a significant portion of mine), and had drank several 100ml of water. Obviously full, it curled up and fell asleep in Dina's lap. Dina's husband was initially not best pleased when she brought him home, but apparently by the time she'd had a shower, it was again asleep, this time in his lap.

27/07/2009 Greece VI: The IGME Ophiolitics

Well, today we had to go into IGME to deposit our 100s of kilograms of rock samples collected so far, and to let Annie do some work. Before returning to Grevena, we decided to take a look at a small ophiolitic mass between IGME and Argilos. Only around 20m thick, the unit comprised lavas, sheared at the base, with sands and a lateritic surface. Not an ophiolite by any stretch of the imagination. Given the lack of shearing in the underlying sediments (which look identical to many of those found in the Zavordhas region), my guess is that the unit may be an olistolith. Certainly it is difficult to believe that the shearing was due to thrusting, given the thickness of the unit and lack of shearing in the upper sections of the unit.

We then returned to the conglomerate we visited a few days ago. Looking at the southern end of the outcrop, it became clear that we had missed more vital clues to the history of the outcrop; isoclinal folding in the Cretaceous carbonates above the ophiolitic conglomerates which look extremely similar to mass flow deposits I have seen in Spain. Before leaving, we checked the conglomerate. Every pebble was polished and striated, and many were faceted. Looking at literature in the evening, I failed completely to find any reference to striation and facetting in mass flow deposits. I still think this is more likely then the fault alternative, but this will need a more detailed study than we have time for here.

Spot the soft sediment fold...

26/07/2009 Greece VI: Passive Activity

Since it has now cooled down significantly, Dina and myself decided to take Annie back to the outcrops studied last year, near Fotino. There's plenty more granodiorite than we thought last year (partially due to my being swayed by the reports of 'pebbles' within some of the intrusives), but some of the faults we found still separate intrusives and sediments, and the partial melting is still extremely interesting.

Definitely a coal seam

Dina had the bright idea that the faults may be graben systems, which seems obvious, but given the core complex conversations we had with Annie and Dimitri before either of us saw the outcrops, it hadn't crossed our minds. I think the idea has the potential to explain almost eveerything we see in the area, and can be combined into a regional picture; that of development of the Triassic Pelagonian Passive Margin. Extension=faulting and shearing=mantle melt=remelting of granitic material and intrusion of basic dykes into the continental basement and overlying sediments. Problem solved?

25/07/2009 Greece VI: Rest day

Well, here I am, sipping Mythos in our air-conditioned cocoon above the baking-hot streets of Grevena. Can you blame me, when it's 42 degrees C outside, and still rising? Annie decided that today would be a good day to catch up with writing, and to prepare for field work over the next week. We're going to look at a lot more ophiolitic blobs, I think. I've been putting my GPS info and the IGME geological maps into GoogleEarth, and all of these blobs are still more than a little bit strange, given that they continue with sporadic but predictable appearances (between the Triassic-Jurassic and Cretaceous carbonates) all the way to the Vardar and beyond. A continuous ophiolitic sheet (over 300km in width) is thought to be pretty much impossible, as there doesn't appear to be a way to transport such a large sheet without major imbrication. In addition, the sediments we saw the other day indicate that the Mesohellenic Ophiolite probably didn't even continue as far as Argilon, let alone the Vardar Zone (unless there's been a huge amount of erosion, of course).

Ah well, no way of solving these problems until we do more fieldwork, so I'm not going to worry about it too much!!

24/07/2009 Greece VI: Fahrenheit 100

We knew today was going to be hot. The weather reports here are all pretty accurate in the summer, and, apart from the odd unexpected local thunderstorm there's very little that isn't predicted.

As a result of the forecasts, we decided to head up into the high mountains to search for ores. I started off by panning in a stream filled with boulders from the high mountains above us, but came up with only a couple of grains of magnetite and chromite. Not exactly a huge shock! We then saw a black crane, which I managed to get a few pictures of before it disappeared (much to Annie's disgust!)

We then moved up towards Vassilitsa, and picked up some Listwanite (gold-bearing in some localities in the world, though probably not here) from the road next to a a ramshackle hut beside which goats bleated contentedly in the green sun-soaked hillsides.


Just above the chalets at the Vassilitsa Ski Park, I managed to find some greenschist facies amphibolite (I can't get away from the stuff) at the base of some beautiful green, red, blue and purple serpentinite). Dina managed to find some mylonitised (now serpentinised) peridotite shot through with quartz veins, which is extremely unusual... apart from that, no real surprises. I forgot my hammer sheath at the listwanite stop, which we returned for after having lunch at a spring on the Vassilitsa road.

Then we journeyed along a scenic route through the mountains to some SSZ basalt and boninitic lavas. While I had another (unsuccessful) attempt at panning in an idyllic alpine stream with only an electric-blue damselfly for company, Dina and Annie bashed at the outcrop to find metalliferous jaspers laced with arseno- and ironpyrites. After three days of rock collecting, the Blazer was pretty full with specimens for museum exhibitions, but this didn't deter us from further loading the vehicle with these glittering blocks.

After our excursions, we made our journey back to Grevena; the automatic Blazer wheezing and revving in the heat, which by now had reached 98F. By the time we arrived back in the town, the car thermometer read a steady 108F. The pharmacy thermometer near to Annie's didn't tell a much better story at 39C. We retreated into the cool, to rest, before Annie, myself and Mike headed out to a very nice chicken restaurant in the evening. A free beer from the lady who owned the place made a pleasant end to a very satisfactory day.

23/07/2009 Greece VI: Portitsa and the strike-slip mystery

Well, today we decided to pay a visit to Portitsa and its bridge (see photo). Before we got there, we took several pictures of the haze, collected some impressive rudistids from Orliakas Mountain, and saw pillow lavas and three lumps of limestone in the Portitsa Valley (which I'm going to call the 'Three Kings') apparently pushed up during strike slip faulting along the boundary of the Mesohellenic. In the valley itself we saw some impressive onion skin weathering in molasse at the base of the limestone cliff (on the path from Spilion) and I did a little panning. It was pretty hot and humid by the river, and so after a brief stop for lunch we made a hasty retreat, taking three dips and strikes of the base of the molasse before returning to the Blazer. None of us believed the temperature inside the car when we arrived back - there's no way it was only 25C!


By the time we got back into the car, we were all quite hungry again. Instead of making the journey all the way back to Grevena, we decided to pay a visit to Aetofolias (the Eagle's Nest) for some food. The last time I was here we were visited by a fox, and I lay on the road in the middle of the night, and stared up as the Pleiades Meteor shower produced a cosmic firework display above my head. It was slightly earlier this time, so no foxes or shooting stars, but I did get to enjoy the gorgeous alpine scenery around us whilst eating loukanika and some delicious karpouzi.

22/07/2009 Greece VI: When is an ophiolite not an ophiolite?

When it's a sheared conglomerate!

Well, the plan was to get to Rodiani today, to have a look at some of the ophiolitic units there. However, having failed to find the correct road from Metamorphosis, we took a trip to one of the random ophiolitic blocks I mentioned in yesterday's post. The outcrop was some 20m high; a cliff face on the side of the road. Thin shales and a thick Cretaceous carbonate sequence capped the unit, which itself was probably underlain by Triassic shelf carbonates. The unit itself was sheared roughly parallel to the Cretaceous bedding, and comprised rounded red cherts, serpentines and extremely weathered gabbros, all within a pale fine grained groundmass (presumably some variety of serpentine). More resistant white bodies made up one layer; this had an undulose base but flat top.

Even our friend mantis religiosa likes a good conglomerate...

In short, nothing like an ordinary ophiolitic mass. Predominantly ophiolitic material, yes. Sheared, yes. But actually a part of an ophiolite? Nope. According to the IGME Siatista Map Sheet, this locality is part of a larger one between the Triassic-Jurassic and Cretaceous filled with material from both the Pelagonian Continent (schists) and ophiolite (cherts, basalts, gabbros, serpentine). I have a feeling that this may be the foreland basin material expected of collision, which would suggest that the Mesohellenic ophiolite either never made it this far, or was completely eroded and replaced with this material before deposition of the Cretaceous carbonates. Which is a problem for geologists invoking a huge Pindos-Pelagonian-Vardar ophiolite. But before I can say anything more, we need to have a look at some more of these ophiolitic 'blobs' stuck on top of the Pelagonian.

21/07/2009 Greece VI: The Return

Yes, I've now been in Greece six times. Athens once (with family), Part IB Mapping, Part II field trip, Part III Project, last year, and this year. It's very much becoming a second home. This time definitely won in terms of number of pieces of transport and length of time 'on the road'; two trains, two planes, and then two buses to get into Kozani. I then rang Annie and Dina, who picked me up nd took me to Annie's office (which is now much spacious and well-furnished than any I've seen in Cambridge). We had a few chats about Dina's wedding, and then got back onto geology. Specifically the problem of the 'ophiolites' between Vourinos and the Vardar Zone.

Whilst the ophiolites in the Vourinos and Pindos region (including, I presume, the Rodiani-Zygosti rocks) have definitely come from the Pindos Basin, there is still uncertainty about ophiolitic bodies further to the northeast, towards the Vardar Zone. The problem is that most geologists have only worked on one zone, and so Vardar geologists all swear blind that Pindos Zone ophiolites come from their region, and vice-versa. I think that it's more likely that both groups are partially right, but this needs to be tested. Anyway, more puzzling to me are the scraps of ophiolitic material between the Vourinos and Vardar regions. The IGME maps have most of these as Palaeozoic, but again there seem to be little evidence for the absolute age. Given Annie and Dina's descriptions of these units as blocks of serpentine (from pebble to house-size), with scraps of cumulates and lavas, I suggested that these may in fact be sediments (conglomerates) coming off the Mesohellenic Ophiolite during collision. Annie wasn't very happy with this idea, but I'm not sure why. Anyway, I'm sure I'll get to see one of these bodies for myself at some stage.

After our discussion, we had another trip in Annie's Landrover before arriving in Grevena at about 5pm local time yesterday (22 hours travelling). Then napped for three hours before going to the nearby fish restaurant for octopus (and very nice it was too). Annie then took herself off to bed, and myself, Dina and her husband, Mike (Annie's son) and Anna went off for a drink before bed. A good start to what is hopefully to be another good trip!