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Choletria is an abandoned (almost) village in Cyprus, about 15 km east of Paphos. There is a new village nearby which is sometimes called Choletria also or Nea Choletria (New Choletria). I am going to show you some photos of the old village (or what remains of it) which was relocated because of earthquakes in the second half of the 20th century.
Xeros Potamos is a river that runs close to the village. This is road here and it is fordable with a small car.
In 1953 an earthquake seriously damaged the village.
Relocation was considered but in the end it was decided to build the village up again.
However, in 1960 another earthquake came and that was more than enough. Village was slowly moved to its new location. The decision was inevitable. What wasn’t destroyed by earthquakes was in a constant threat because of landslides.
The slopes of the river valley are very unstable…
…because of this – bentonite clay. White is chalk. Bentonite was originally volcanic ash that weathered into clay minerals, mostly montmorillonite that swells when getting wet and contracts while drying.
This is what may happen to the clayey slope when it rains.
It isn’t very good idea to build houses on it. Bentonite is obviously easily erodable but it is also highly susceptible to liquefaction when saturated with water. It only takes some shaking (earthquake) to turn formerly more or less solid soil into liquid.
In addition to bentonite, chert (left) and marly chalk (right) are abundant as well.
Choletria is a sad example of a settlement that should not have built where it was. However, someone here seems to disagree. Well, the view is nice and neighbors are far away. Perhaps its worth the risk, who knows?
By the way, the latest relocation is not the first one in the history of Choletria. It was originally located on the coast but its inhabitants decided to leave because of frequent attacks by seaborne Saracen pirates. Unfortunate history indeed.
The accretionary Wedge #45 is about geological pilgrimage – the sacred geological place that you must visit at least once in your lifetime.
I know I am a bit late and I am going to violate the rules of the game because I do not wish to pick a single location. Instead I am thinking about a huge and geologically extremely versatile landmass – the western part of the USA.
Many among my readers would now say: wait a minute, shouldn’t it be a remote and relatively inaccessible place? But for me it is both remote and inaccessible. It is remote because I live far away and it is inaccessible because I should go for a very long trip to see a tiny fraction of the places I’d like to visit there. I have never set my foot on US soil. Not because I can’t do it for some reason but I just see no point in going to New York for example for some days. I am not interested in it. If I am going to make a trip to US, then it should last some time to justify the money spent on airplane tickets, etc. It is very hard to do because of other commitments in life. It is much easier for me to take a week and visit some geologically interesting place in the Mediteranean area, for example. The Med, by the way, is very interesting as well.
There is one aspect of US geology what makes me jealous. No, I don’t mean Grand Canyon, Yellowstone, or other places with spectacular geology. Its the fact that USA is a country where people share a common language and taxpayers money adds up to initiate something big. There are projects like “Roadside Geology” series of books for every state and digital geological maps available free of charge. There is nothing like that for Europe. Europe is composed of small nations, everyone speaking their own language and dealing with their own small and globally absolutely unimportant projects. GPS was not accidentally created in the USA, it is easy to understand why it didn’t happen in Europe.
Yes, I know, Europe may be culturally richer because of versatility but I do not see much value in it. It really disturbs me that for every country geological guides that are in existence are written in strange languages understandable to few millions only and they are mostly printed, very little is available in the web. Every geological survey has their own mapping rules. Even if you can access some of their maps, the coordinate system used is often local and usable with great difficulties, if at all.
My geological pilgrimage would ideally take a year at least, possibly even more and involve many stops in California, Arizona, Utah, Oregon, etc. I doubt I will ever make it because it means I have to take a year free of other commitments but who knows. It costs nothing to dream and things you would like to do very much sometimes happen.
Slickenside is a striated and polished face of a rock. Slickensided rocks are common in tectonically active areas because they are formed by frictional shear during movement of fault surfaces relative to each other.
The example above is from Cyprus. I stumbled upon it accidentally. It just lay there in the high grass waiting to be discovered. The chance to be discovered by a geologist is actually pretty good because the area surrounding the rock is extraordinarily rich in varied geology. There is an exposure of tectonic mélange, chloritized lava, exposure of trachyte with large sanidine phenocrysts, and pillow basalt within a rectange of a few hundred meters. Only few kilometers away are a hill made of serpentinite, a village (named Choletria) severely damaged by an earthquake, and bentonite which played a role in the destruction of the aforementioned village, and many more interesting rock types like chert, chalk, etc.
There are no signs directing to these interesting places. I am often astonished how little most people care about geology. Of course, this isn’t going to change. Rocks will remain boring for the majority of people in the future just as they are now but nevertheless I couldn’t stop thinking about how the place might look like for example 100 years from now. I think there is a good chance that it is a geopark with nature trails and lots of explaining info boards. There is lots and lots of potential for it in the region between Nea Choletria and Nata.
Pillow lava is a lava flow that forms underwater, usually at the bottom of the oceans. Individual pillows are mostly up to one meter in diameter.
Pillow lavas are extremely common on the Earth’s surface — they form the upper part of the oceanic crust but we have a chance to see them relatively infrequently because very few of us have ever visited their natural birthplace.
Sometimes though they get pushed on top of the continental crust for us to take a look. One very good place to admire pillow lavas is Cyprus. The Troodos ophiolite which makes up large part of the island is a complete section of the former ocean floor. Hence, pillows are common in Cyprus.
Pillow lavas may show radial cracks (when you have a chance to see the cross section). These cracks are similar to cracks in columnar basalt. The cracks are perpendicular to the margin of pillow, that’s why they are radial. Cracks in columnar basalt are parallel because they formed in a lava flow that cooled as a sheet. Another common feature of pillows are chilled margins. This is very fine-grained or glassy outer part of the pillow which cooled very rapidly in cold seawater. This material is called tachylyte. Some of the pillows below show radial cracks and some have chilled margins which may be altered to palagonite.
Until I visited Cyprus I had seen pillow lava in pictures only. But there I saw it almost every day, often unintentionally while looking for something else. It was even easy to get bored of pillows but I tried to remind myself that as soon as I will go home there are pillows nowhere near, so I took many photos. Here are some of the pillows I saw in Cyprus:
Pillow lava near Choletria.
Pillow lava near Fasoula.
Pillow lava near Fasoula.
Pillow lava near Fasoula.
Pillow lava (in the middle) near Petra tou Romiou.
Pillow near Petra tou Romiou.
Pillow near Petra tou Romiou.
Pillow lava in the Mathiatis open-pit mine.
Pillow lava in the Mathiatis open-pit mine. Note radial cracks.
Pillow lava in the Mathiatis open-pit mine.
Pillow lava in the middle between dikes along the Akaki River.
Pillow lava along the Akaki River.
Pillow with a chilled (glassy) margin (Kamara River).
Pillow lava along the Kamara River.
Pillow lava along the Kamara River.
Pillow lava along the Kamara River. Black chilled margin is partly preserved.
Pillow lava near Arediou (along the Akaki River).
Pillow lava near Arediou (along the Akaki River). Former chilled margin is altered to orange palagonite.
Pillow lava breccia near Arediou (along the Akaki River).
Pillow lava near Arediou (along the Akaki River) with palagonitic rim.
Pillow lava near Arediou (along the Akaki River).
Pillow lava near Arediou (along the Akaki River) with radial cracks.
Twinning is common in gypsum crystals which often results in beautiful swallowtail habit.
I saw very nice exposure of swallowtail gypsum crystals in Cyprus. The crystals are several meters long and they all seem to be twinned.
These crystals formed in a shallow hypersaline lagoon in the Messinian (the last stage of the Miocene) about 6 million years ago. I have also written about laminated gypsum that is exposed nearby and formed roughly at the same time but probably in somewhat deeper water.
Twinned gypsum crystals (selenite) in Cyprus near Elediou. I know some of you might be worried about the hammer but I can assure you that I used it for scale only. I always carry it in my backpack when geologising and use it more often for scale (if pen is too small) than for smashing rocks. I would not consider destroying an exposure as beautiful as this and I very rarely attack outcrops at all. However, I do collect and often smash loose rocks.
I am now back home from Cyprus. It was very interesting geotrip and I will definitely use material collected there (sand, rocks, and photos) in many more posts in the future. For some time my posts will remain short because my time is very limited. If I’ll feel the urge to write, I should write my masters thesis instead. However, I do not want to abandon my blog. Maybe not daily but several times a week at least I will post some photos with brief comments.
Petra tou Romiou (the Rock of Romios) is a large white rock at the southwestern coast of Cyprus. The rock is very famous because Aphrodite (the goddess of love) allegedly borned from the waves here. Right now it seems to be a magnetic spot for those who have fallen in love or are just married.
The name of the rock, however, has nothing to do with Aphrodite. Romios was a byzantine folk hero who used this rock to hurl at the pirates.
I visited the place for a strange reason — I just wanted to know what type of rock it is and to take a look to see whether I notice something geologically interesting.
I did find out that the rock is a limestone breccia and there are nice grooves on the upper part which look like slickenside. Slickenside is a smooth and shiny polished face of a rock, the result of a friction between two moving blocks of rock.
This probably indicates that Petra tou Romiou was once part of a tectonic mélange. This is a mixture of very different rocks (accretionary wedge) which is pushed on top of the edge of the continental margin by the subduction process. The same process probably also brecciated the rock which was originally a reef grown on volcanic oceanic islands. There are volcanic rocks nearby, including pillows, which lend support to this hypotheses.
Petra tou Romiou. I did find out that the rock is a limestone breccia and there are nice grooves on the upper part which look like slickenside. Slickenside is a smooth and shiny polished face of a rock, the result of a friction between two moving blocks of rock.
Petra tou Romiou is composed of limestone breccia.
Slickenside on Petra tou Romiou.
I visited today a place that is truly classic geological site in Cyprus. That’s what my geological guidebook says which I highly recommend if you are going to Cyprus for a geotrip. The book is titled „Cyprus“ and it is part of a „Classic Geology in Europe“ series. The photo of the outcrop described below is on the cover of the book.
This site is an outcrop of hyaloclastite with pillow basalt above it and both of them are cut by a swarm of dikes. It truly looks spectacular and there is a very appropriately placed hill on another side of the river running before the outcrop that offers very nice view to the scene.
Hyaloclastite in the middle, pillow basalt on top of it and dike swarms cutting both of them.
Elongated vesicles in the dikes clearly indicate that the magma moved laterally, not just vertically upwards.
Hyaloclastite is a glassy volcanic material which probably formed by the underwater fire-fountaining.
Pillows about 50 meters away along the river.
Cyprus is one of the few places where rocks from the mantle crop out at the surface. They are not part of the mantle anymore, of course, but they were during the formation. Seeing mantle rocks and walking through moho (boundary between the crust and the mantle) should definitely be in every geologists lifetime list. I am very glad I did it today.
Me holding a piece of the mantle (harzburgite) in my hand.
Harzburgite is the main rock type of the deepest exposed sections. Harzburgite is a peridotite (ultramafic rock) that is composed of olivine (brown) and orthopyroxene (greenish brown reflective crystals) with minor chromite. Harzburgite is a residue of partial melting (take basalt or gabbro out of the mantle and harzburgite is what remains).
Dunite is an ultramafic rock that is composed almost exclusively of olivine. Dunites here usually contain some orthopyroxene as well and there seems to be a gradational transition from dunite to harzburgite.
Orthopyroxenite (ultramafic rock that contains almost only orthopyroxene) forms layers in dunite and harzburgite. Here is orthopyroxenite layer on top of dunite block.
Littlebit higher (stratigraphically but also topographically) there is a boundary between the crust and the mantle (moho) which is represented by layered cumulates.
All the rock types are partly hydrothermally altered (serpentinized). Here is a block of serpentinite on top of harzburgite.
Cyprus is a mountainous country which makes sights like this common. It wasn’t the first one that day. I saw two slumps in a row and when the third came I wanted to stop and take a picture. I was driving down from the Troodos Mountains towards Paphos in the western coast. The brownish outcrop is part of a heavily weathered sheeted dyke complex which is a part of the ophiolitic sequence (rocks making up oceanic crust).
This is fluvial (river-channel) deposit from the Pleistocene near the village of Kouklia in southwestern Cyprus. The large boulders are mostly gabbro and diabase. These rocks were carried here from the Troodos ophiolite which is about 30 kilometers upstream.
There are several layers with different grain-size. Layer of coarse sand and gravel is between two layers of conglomerate. Below the fluvial sequence is a layer of marly chalk.
I think it is pretty safe to say that today was the best day I have ever had as a geologist. I am hiking and driving around Cyprus. This island is a real paradise for geologists. I highly recommend to visit Cyprus if you are interested in spectacular and quite easily accessible geology. Here is the list of geological stuff I saw today:
mélange
mass wasting (several nice examples)
chloritic green lava
amphibolite
trachyte with sanidine phenocrysts
pillow lava (I saw pillow lava in three different locations!)
slickenside (at least three sites)
serpentinite
serpentinized harzburgite
mudstone (several locations)
thrust fault
quartz and chalcedony veins
earthquake-damaged houses
river-flooded road
chert
calcarenite
marl
bentonite
calcite druse
folds in several locations
fluvial sediments (conglomerate) in several locations
gabbro and diabase clasts in conglomerate
sandstone
limestone breccia
lava flows
amygdaloidal and porphyraceous trachybasalt (as lava and pillows)
It took the whole day which I had at my disposal because I did it all alone. It’s easier that way because I had no distractions and didn’t have to worry about someone else who most likely isn’t addicted to geology.
I bragged about pillow basalts. To back my words I will post some photos of the pillows I saw today:
Olivine tholeiitic pillows near Fasoula (SW part of Cyprus).
Triassic pillow basalt (actually trachybasalt) at the southwestern coast of Cyprus (1 km east of Petra tou Romiou).
Same outcrop 1 km east of Petra Tou Romiou.
I haven’t written a post for several days. I actually have an excuse. I am geologizing in Cyprus. I have gathered some nice material for future posts and hope to see much more in the remaining seven days.
I’d surely like to write a blog as well but internet connections aren’t so easy to find here. My hotel room, for example, doesn’t have such a luxury.
I came here mostly to see the world-famous (among geologists) Troodos ophiolite complex. Unfortunately, the most special part of it (rocks from the mantle) are still snow-covered. They are exposed in the mountains just around the highest peak of Cyprus.
This is a major disappointment to come here from cold and snowy Estonia just to discover that people here are skiing as well. But this means that I have more time for other parts of the island. There is so much more to see. Geology in Cyprus is varied and well exposed.
I won’t promise but I will try to post a photo with short geological explanations every remaining day of my trip. These photos are taken during the past few days here in Cyprus.
Take a look at the beautiful swallowtail gypsum exposure as well that is located only about 100 meters away.
Laminated gypsum from the Messinian (5…6 Ma). This episode is known here as the Messinian salinity crisis. The Mediterranean was isolated from the Atlantic, its water turned hypersaline and large evaporite deposits (gypsum here) formed.
 Pothole in a riverbed (more than half a meter across). Photo taken in Norway. Pothole is a vertical, cylindrical erosion feature in a riverbed (most commonly).
Potholes have variable sizes in the range of several dm to a few meters in extreme cases and they are commonly more deep than wide. I spotted several potholes in Norway in a dry part of the riverbed, one of them is shown above.
How do they form? We need rapidly flowing water that is capable of carrying coarse sand, pebbles, or boulders that are whirled around in the depressions of the rocky riverbed which slowly do their grinding job. You can see many of them resting on the bottom of the pothole. You can even see small grooves on the sides of the pothole which show how the pebbles move once they are trapped inside the pothole.
Potholes aren’t rare but we need several things to happen in one place to see them. The river has to flow rapidly, the river should preferably flow on the bedrock, and perhaps it would be better to have a relatively easily erodable type of rock (limestone should do well). Finally, the potholes have to be dry sometimes. Otherwise, we won’t spot them.
 Pegmatitic igneous rock from Tredalen near Larvik. Gray is nepheline, yellowish brown is wöhlerite, black is hornblende, pink is K-feldspar, and gray is magnetite. The width of the specimen is 14 cm and it belongs to the Museum of Geology of the University of Tartu. This rock sample from Norway is texturally pegmatite (very coarse-grained igneous rock) but the composition is pretty unusual. There are small amount of pink K-feldspar that is the dominant component of granitic rocks but here much more dominant seems to be gray nepheline which is a feldspathoid group mineral. Feldspathoids form when there is not enough silica to form feldspars, let alone quartz which is entirely absent.
Similar rocks are often described as syenites but this is not correct because the feldspathoid/feldspar ratio is too large. This rock sample should be named foidolite according to the QAPF diagram which is commonly used to classify plutonic rocks. Even more precise term is nephelinolite because the dominant feldspathoid is nepheline.
Other notable minerals besides nepheline and K-feldspar are black hornblende, dark metallic gray magnetite, and yellowish brown wöhlerite. Wöhlerite is a pretty rare silicate mineral that occurs in silica undersaturated rocks like the one above.
Celestine is a sulfate mineral (SrSO4).
Celestine is similar to another and more common sulfate mineral barite (BaSO4). Celestine is less dense but their crystals may be very similar. There is a continuous solid solution between the two. Celestine is the principal source of strontium. The other major strontium-bearing mineral is strontianite (SrCO3) which belongs to the carbonate group but it isn’t usually exploited as a source of strontium.
Celestine is found disseminated in carbonate rocks or sandstone. Tabular crystals are found in cavities and veins. Celestine also occurs in evaporite deposits.
Is there anything celestial about celestine as the name seems to suggest? Yes, celestine crystals may be bluish as the sky because of impurities but this color is actually not very typical. Perhaps the first crystals described were bluish but overall this name is a misnomer. Celestine is usually colorless or white.
The celestine druse below comes from Yates in England. The Sr was released during the dolomitization of originally aragonitic sediments. The Sr was released because dolomite can hold only 200…600 ppm of strontium while aragonite can hold up to 8000.
Strontium extracted from celestine is used in pyrotechnics. The beautiful bright red colors in the sky of New Years fireworks are caused by strontium compounds. Because of that, the term “celestine” may not be such a misnomer as it first seems to be.
 Celestine druse from Yates, England. The width of the specimen is 10 cm. The specimen belongs to the Museum of Geology of the University of Tartu.
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