How can you hide a volcano? Apparently, making it the highest mountain on the continent is a good start. Mount Elbrus is both Europe’s tallest mountain and Europe’s highest working volcano. The first fact is commonly recognized, and can be readily found on-line and off-line, but the second fact is harder to locate. While Mont Blanc’s standing as Europe’s highest mountain has long been overthrown, Etna remains on its pedestal, and its label as the tallest volcano within continental Europe is confirmed by sources as authorative as the BBC, Yahoo, and crossword365.com. Arguments are thrown about: Elbrus’ European credentials are questioned (but never when it is just a mountain), or it is considered too inactive to qualify (in spite of being as active as Vulcano itself). Perhaps it is just because it is in Russia, and not nearly as accessible as Etna?
Between the Black Sea and the Caspian Sea is one of the wonders of Europe. Located in a stunning mountain chain, Elbrus stands above it all. This is the volcano that couldn’t stop growing. 300,000 people visit it each year, and each year it kills some tens of them. The people are drawn in by the beauty, the challenge, and perhaps also by the danger. And now geologists are taking a new interest and are finding signs that this volcano is restless. It is well worth taking a closer look.
The Caucasus is a tell-tale sign of a continent in collision. It is a narrow mountain chain, 1300 kilometer long and running from the Black Sea to the Caspian Sea. To the south is the fascinating country of Georgia, with its fabulous ancient monasteries, its lively capital and slightly dubious but ancient wines, grown here for over 6,000 years. To the north are the endless steppes of Russia. Look harder and you’ll see that there is a second mountain chain. The one usually mentioned is the Greater Caucasus, but 100 kilometer to the south between Georgia and Armenia is a second chain, 600 kilometer long, called the Lesser Caucasus. The whole area remains tectonically active: there are numerous earthquakes, mostly minor but not invariably so. The largest one in recent years was an M7.0 in Georgia in 1991 which caused considerable damage. Similar-sized earthquakes were reported in the Greater Caucasus in 1742 and 1350, and in the Lesser Caucasus in 1899 and 1088; a particular devastating one appears to have occurred in 1139.
The crest of the Greater Caucasus is an almost impassable barrier, and came to define the borders of many empires. Especially the southern slopes in the western part receive rather a lot of precipitation, 3-4 meters per year, largely as snow. The moisture here comes from the Black Sea. There are 1500 km2 of glaciers, now rapidly retreating due to the rising summer temperatures.
The central area of the Greater Caucasus has the highest peaks. There are 8 peaks over 5000 meter (discounting satellite peaks). The Lesser Caucasus tops at just over 4000 meter. Mount Elbrus towers over them all: at 5642 meter it is over 400 meter taller than the next highest, Gora Dykh-Tau. Elbrus is also the only one of the highest peaks that is not located on the high central ridge of the Caucasus. It has grown up about 10 kilometer to the north.
Mount Elbrus is instantly recognizable by its shape because of its double peak. There are other examples of such shapes in the area. The highest peak in the Lesser Caucasus is Mount Aragats, in Armenia, 4,090 m high. It has four separate peaks, imaginatively called the Northern, Western, Eastern and Southern peak. Like Elbrus, Aragats is a volcano with holocene eruptions, and like Elbrus, it is slightly off the main chain of mountains. The other 5km+ volcano here, Mount Ararat, is also a double, although in its case the second peak is a mountain in its own right, 13 kilometer away. These three are compound, polygenetic volcanoes. The magma chambers are strong and stable, channeling their output to the same small area over long periods of time, but with more than one outlet.
But is it Europe?
Both Aragats and Ararat are Asian volcanoes, whilst Elbrus is counted as European. Of course this depends on where the border between Asia and Europe is assumed to be, which to some degree is an arbitrary choice. Borders of regions tend to follow mountain chains or rivers. Nations, of course, prefer this because these features aid border security. Along the southern border of Russia, the watershed of the Caucasus is the most suitable feature, and the border between Georgia and Russia runs (apart from some disputed regions) over the tops of the mountain chain. Mount Elbrus is well to the north of this, and thus falls within Europe (and within Russia).
But there have been different conventions in the past. The Greeks, in the 6th century BC, put the continental boundary along the rivers Volga and Don, north of the Black Sea and the Caspian Sea. They would have considered this to be the ultimate border of civilization. With some minor re-drawings, this convention remained until the late 18th century, when a German textbook proposed the Kuma–Manych Depression as the natural border, as the lowest point in the region. This choice did expand Europe to the south, but had the disadvantage that it isn’t a clearly defined line, but a fairly broad valley. Since the late 19th century, the Caucasus has been taken as the continental divide, although in the Soviet Union the Kuma–Manych Depression remained the official definition until the 1950’s. It is notable that the expansion of Europe followed the conquest of the region by Russia – where Russia went, Europe followed.
And so, over time, as the border shifted southward, Mount Elbrus came closer and closer to Europe, until it finally jumped across. The ancient Greeks would have considered this as leaving civilization. In modern days, the European credentials of Mount Elbrus are strong, and the discussion is about when, not if, it became European. No significant challenge has been made, and Elexit (Elbrus-exit) is not on the cards.
The term ‘Caucasian’ is used for light-skinned people, suggesting that these came from here. But this is far from the truth. (Note that ‘Caucasian’ covers a range of skin tones.) During the ice age, an isolated group of hunter-gatherers appears to have survived in the region. After the ice age, their genes became incorporated in the migration that brought the Indo-european languages to the west, argued to be by horse-riding hunter-gatherers from the Caspian area. But the same Caucasian gene pool also contributed to the neolithic farming invasion, spreading from the Fertile Crescent. The Caucasus acted as a divide between the two flows, but both picked up genes from here. Many migrations passed through the area, and peoples came and went. This left its trace: the language diversity is huge, with four language families (Caucasian, Semitic, Indo-european, Turkic) and 50 or more individual languages. In addition, there is also a Mongolian language, not part of the four families, which survives here. It is a tribute to the huge variety of people passing through and settling at this cross roads of the continents. There are some 3-meter tall megaliths and smaller dolmens here, which may date back to the Scythians, invading from the west, or which may remember other, forgotten peoples. Here are some of the most ancient churches and monasteries in the world, but also some of the oldest Islamic places. The Mongol hords passed through on their way to Egypt. It became the border of Kublai Khan’s empire, and afterwards the border of the Golden Horde. A powder keg it always was.
Nowadays, Mount Elbrus is in the Kabardino-Balkar Republic of Russia. The local population consists of Adyghe, Balkar, and Russians. The Adyghe, or Circassians, had some reputation. A British traveler in the 1830’s wrote: “The sole pursuit of the Circassians is predatory war against their neighbours” and “a martial people, trained from infancy in the midst of arms and early habituated to systematic plunder”. They were displaced after the Russian-Circassian wars, when over a million may have died. The opponents were no less brutal. Leo Tolstoy, who was in this war, wrote “It had been the custom to rush the auls [mountain villages] by night, when, taken by surprise, the women and children had no time to escape, and the horrors that ensued under the cover of darkness when the Russian soldiers made their way by twos and threes into the houses were such as no official narrator dared describe.” Since the Circassian genocides of the 1800’s, the majority of their population now live in Turkey. They speak a Caucasian language. The Balkar are indigenous people from further to the east along the Northern Caucasus, where they have lived since at least 1100. The closely related Kardachay Republic uses Mont Elbrus as its emblem. Both the Kardachay and Balkar are Turkic people, who spread from Asia during the 6th century when the Turkic empire stretched from Mongolia to the Black sea. The entire Balkar population was deported to Siberia and Kazakhstan by Stalin; the survivors were only allowed to return a decade later. The Russians arrived with their century-long conquest of the region, which ended in the 1860’s.
This area has been a melting pot, shaped by war. The dreadful reputation which predates the Russian invasions are perhaps an indication that the local resources were limited and trade was difficult. Mountainous regions, in the days before tourism, were invariably poverty-stricken. But this area also always felt the brunt of the waves of invasions from the Asian steppes, from the Huns to the Mongols, and self-defence may have played a role.
And Mount Elbrus became an unlikely battle field in the second world war when German armies got sidetracked by trying to conquer the mountain. As in so many places in Russia, a monument has been erected in memory of this war. Understanding the Russian mindset, and its melancholically-inclined culture – and beautiful singing – begins with seeing the devastations brought in the second world war. Although, it is recommended not to inquire too much in how much of the devastation was self-inflicted by the merciless regime of the days.
Mount Elbrus includes both the highest and the second highest peak in Europe. The two summits are about a mile apart. The Western summit is the highest, at 5642 meter. The Eastern peak is marginally lower, at 5621 meter. In between lies a shallow saddle, at an altitude of 5416 meter. The Eastern peak is the youngest; it has a crater bowl around 300 meter in diameter and 80 meter deep, but it is filled with snow and ice and the true summit can be hard to locate. The crater is open to the east, from where a long lava flow has descended. The Western summit is much older and is eroded; a vertical fault has removed part of it. The summit is at the northwest rim of a 250-meter wide crater. A small pyramid identifies Europe’s highest point. A minor fault crosses the two summits, and a number of small volcanic cones lie along this fault, in the river valleys towards the west: this fault has clearly been hijacked for magma transport.
Mount Elbrus is built up from dacite lava breccias and rhyolite tuff, covered by extensive lava flows. Most of the Holocene lava flows descend steeply into the river valleys and consists of rough, viscous a’a lava. But the more recent cover also includes significant explosive debris. The longest recent lava flow runs 24 kilometer to the north-northeast, from the Eastern summit. There are some fumaroles at the Eastern summit and along the flanks. All indications are that the activity has moved from West to East, and the Western peak may be largely extinct. The Eastern one seems very much alive.
Mount Elbrus is covered in tens of glaciers, not surprising in view of its height and location. The glaciers are now receding, and in places are thinning by meters per year. It is part of the world-wide decline in glaciers, related to summer temperatures. But especially on the Eastern summit, there may also be some melting due to increasing ground heat. The glacial retreat has caused lakes to form on surface previously covered in ice. In 2006, a glacier dam broke through and one of the newly-formed lakes caused a flood down the mountain, destroying a resort. Luckily this happened at night when there was no one at the resort.
Mount Elbrus is secure in its status as the largest volcano in Europe. But is it active, or is it extinct? Should it be placed above Etna in the European rankings, or is it just a mountain with a volcanic legacy but no activity? This is another fairly recent change in our knowledge. Previously, it was considered inactive, doing nothing of interest since the Pleistocene. But in the 1980’s this view changed, and evidence for much more recent eruptions was found. In the 1990’s, it changed status to potentially active, and according to some, pre-eruptive. But let’s first look at its older legacy.
The volcanic activity in the area goes back some 8 million years, but it was not always at the same location. Over the past million year, the activity migrated slowly to the west, until the story of Elbrus-proper began around 340 thousand years ago. This is the age of the oldest well-dated deposits which left ignimbrites hundreds of meters thick, exposed in the various river valleys. The early caldera cycle ended 250,000 years ago with a large explosion which levelled the newly-built mountain and created a caldera 17 by 14 kilometer diameter, 230 km2 in area. It is still (just about) visible in the landscape: Mount Elbrus grew up inside this caldera. Much older ages for this caldera, in excess of 600,000 years, have also been proposed. After the caldera formed, a resurgent dome formed, but otherwise the area went rather quiet.
Eruptions, both magmatic and explosive, resumed 170,000 years ago, when over time 2 kilometer thick lava build up a new edifice. The current structure was in place by 60,000 years ago. There have been eruptive cycles since, both in the pleistocene and the holocene.
The volcano structure is not as tall as it may seem. The base of the volcano is 3500 meters high, and only the upper 2 kilometer of Elbrus is the actual volcanic cone. It is about 15 kilometer wide, and thus fits neatly into the old caldera.
The modern cone is clearly the same volcano as the one that caused the caldera. Over that time the magma outlet has hardly moved. But the composition of the magma has changed. The oldest lavas consisted of around 60% mantle material and 40% crustal melt. The newer deposits have 80% mantle and 20% crustal melt. Thus, over time the mantle has become more dominant for the source material of Elbrus.
Although currently quiet, this volcano is no longer considered extinct. Volcanic debris provides evidence for at least four strong eruptions of Elbrus over the past 7000 years. But dating these has proven difficult. Much of the lava came out at altitudes over 3 kilometer, where no vegetation grew and therefore radiocarbon dating lacked carbon to work with. The various sites describing Elbrus normally state that the last eruption took place around 50 AD, a claim that comes from an older paper. But it is not that simple.
Carbon-containing materials have now been found underneath or embedded in some of the lava flows, sufficient to allow for radiocarbon dating. The earliest attempts showed three episodes: the oldest (7200-7500 years ago), the middle (4600-5500 years ago) and the youngest (around the year zero).
Subsequent dating of fossil soil and charcoal found ages of 6250 ± 50, 4270 ± 40, 1330 ± 80, and 990 ± 60 years BP. Other authors find different dates, with major eruptions 39±5, 28±3, 23±2, ∼21, ∼9.2–9.3, ∼7.8– 8.0, ∼7.2, ∼6.0, ∼4.9, and ∼4.6 thousand years ago and during the first and second centuries A.D. Two fairly accurate measurements have come from carbon dating of paleosoils, covered by volcanic debris in the river valleys. The debris was washed down by the river, after its flow was dammed by lava. The buried soils were dated to 6410±100 years ago and 1780±70 years ago. The first date is consistent with the 6250 ± 50 event, and the second one was probably the event dated previously to 50 AD or the 1st and 2nd century AD. The radiocarbon dates suggest that the mountain has erupted since, as recent as 1000 years ago.
But there has been further, undocumented activity. An ice core going back around 500 years showed a number of volcanic horizons, including one from Katmai 1912 and one from a large eruption in 1840. But there was also an (undated) local event, as shown by inclusions of grains which could not have traveled far. This shows that the mountain was active within the past 400 years.
Dislocations in surface features show that over the past 7000 years, there were also at least five earthquakes with a magnitude of M = 6.5–7.0. The eruptions and earthquakes do not coincide in time: the area is both volcanically and tectonically active, but the two appear not related. Paleosoils associated to earthquake dislocations have been dated to 5600, 3900, 2400, and 1600 years ago. The vertical displacement of the last event was at high as 3 meters. All of the events were accompanied by large rock avalanches. There is also evidence for simultaneous damming of rivers in the area, at a time that could be coincident with the Terek earthquake which took place in the North Caucasus around the year 1688, and may have been as large as M6.5.
The magma chambers
Evidence that Mount Elbrus still has an active magma chamber was published only in 1984, when a magma chamber was suggested to reside at depth of 0.5km-2km below sea level.
Seismological studies have measured the seismic velocities underneath Elbrus. Low velocities indicate melt. As expected, there were low velocity zone underneath Elbrus. But there was another one to the east: not all magma here is Elbrus.
The picture shows a study by Rogozhin et al., 2016. The grey lines are gravity contours. They show a strong negative anomaly (so low density rock), a little to the south of the peaks of Elbrus. The suture zone (fault) to the north is an active earthquake zone, but due north of Elbrus it shows a gap, probably due to melt which reduces the stress in the zone. The open circles with the central dots show the volcanic craters. Two are on Mt Elbrus itself, and three are to the east. The black dots show where the seimographic data was taken.
The picture shows the cross section along the line of the black dots. Elbrus is on the left. Red areas indicate low velocities: this is seen underneath Elbrus, and underneath an area to the far right. These are the main magma chambers. Clearly, there is a significant amount hiding at depth.
But where did the magma come from? The wider Caucasus does not have that many volcanoes. It feels a bit like Mars: there relatively few volcanoes but the ones that do exist have grown huge. In fact, volcanoes are not usually present in collisions between two continents. The mountain chain that forms is a long crumple zone, but continents do not subduct and therefore the bottom is much less deep than in mountains which form from oceanic-plate subduction. That means that not much melt forms. You get granite (lots) but no magma. Neither the Pyrenees, the Alps, nor the Ural (Europe’s other continental collisions) have volcanoes. The Himalayas does have a little volcanic activity, but that mountain range is huge with very deep roots. So why does the Caucasus have volcanoes?
An indication comes from the fact that the major volcanoes, Elbrus, Kazbek, Agragat, and Ararat, are all located along the Trans-Caucasus transverse uplift, a broad zone that runs roughly north-south perpendicular to the mountain chains. Elbrus lies along its western edge, and Kazbek along the eastern edge. This region appears to show some extension, and this extension may be source of the magma.
It remains unclear why in this large region, only a few major volcanoes have grown up, rather than more smaller ones. It appears plausible that the magma generation rate is too low to reach the surface by itself, but requires tectonic faults to provide a pathway. The main volcanic centres indeed appear to be associated with a few major tectonic faults.
There has been more significant volcanic activity in the past. Between 2 and 3 million years ago, an area on either side of the Lesser Caucasus was flooded with basalt. This has been called the youngest and smallest flood basalt province on Earth. It runs from northeast Turkey to northern Armenia (a volatile region at the best of times), covers an area of around 15,000 km2 and an eruptive volume of around 2250 km3. This is what fertilized the Fertile Crescent: the Garden of Eden grew on a fissure eruption. The current collection of massive volcanoes are little more than the explosive afterthoughts.
In the 1970’s, an astronomical observatory was build on the southern slopes of Elbrus, at a height of 3100 meter. The main instrument is a 2-meter telescope (the size refers to the diameter of the mirror), and there are several smaller domes with telescopes up to 60 cm, used for research ranging from the Sun to extrasolar planets. It is an impressive location, and the hike up from Terskol village is popular with visitors, and commonly used as an acclimatisation hike before climbing Elbrus itself. The observatory was run as a joint institution of the Ukrainian and Russian academies of sciences, but in these more troubled times the agreement apparently is on hold. The world of science cannot remain entirely independent of politics. The observatory is now solely run by Russia.
This is currently not advised. The UK Foreign Office advises against all but essential travel to Kabardino-Balkaria, and this includes the Elbrus area. The area is not as dangerous as it was a decade ago, when terrorist attacks spilled over from nearby Chechnya, but a risk remains and kidnapping is also a real threat. If you still want to go, be aware that getting the visa can take a few months. The permit for the park costs 50 rubles, to be paid locally. Check that the travel warning does not invalidate your travel insurance. And use a reputable travel company with experience in the area.
Mount Elbrus is one of the ‘seven summits’, the highest summits on each of the continents. The full list is Kilimanjaro (Africa), Denali (North America), Elbrus (Europe), Aconcagua (South America), Carstensz Pyramid (Papua, Oceania), Vinson (Antarctica); Everest (Asia). As an interesting side, Elbrus is the only one of the seven liable to erupt underneath your feet! In spite of this, and in spite of the travel warnings, it is in high demand by people wanting to conquer at least some of the seven. The climbing season runs from May to September. During July and August it can get busy on the mountain. The climb is only of moderate difficulty but the height requires acclimatisation and ability to handle snow and ice, and the ascent is long – and don’t try to kill your guide. And like Everest, people do die on the climb most years, in fact it has a very high ratio of fatalities to climbers, perhaps because the mountain attracts novice mountaineers with its promise of smooth slopes. 20 fatalities per year is not uncommon!
The usual approach is from the southern side, uses tracked vehicles to get to base camp, climbs to get up to Lenz Rocks camp, and from there the summit assault is done in a single, long day. If the weather is not too great, the summit day can be done from the High Camp but that makes for a very long and hard day. If you are not up to the full climb, a Snow Cat can be used to get up to the saddle between the summits, from where you can join the climbers. For the adventurous, the descent can be done on skis. The north side can also be climbed but this is significantly harder, involves camping rather than using huts, and requires a high level of fitness.
The mountain remains dangerous. Even if not erupting, it has a habit of killing the people trying to conquer it. It also goes after the people who committed the crime of living nearby. On September 1 this year, a mudslide hit the town of Elbrus and although fatalities were light, the entire area had to be evacuated including both Terskol and Elbrus. Both the main road and the gas pipelines were badly damaged in multiple places. The evacuations were done by helicopter as all roads had become blocked: over 1000 people were carried to safety this way to the nearby town of Tyrnyauz . 40 tour groups became stranded on the mountain, including 12 groups of foreigners. And this was not the first such event. On August 14, Tyrnyauz had itself been hit by a large landslide, necessitating an evacuation. This is not a mountain that takes disturbance lightly! It demands respect.
And one day, perhaps soon, perhaps not, Elbrus will again respond to our intrusions with fire, ash and smoke, and lava will come flowing down the glaciers. What a sight it will be, to see Europe’s highest summit burst in flames. One day.
And to end, perhaps not the best ever view of Elbrus, but a low-res copy of one I took myself, 30 years ago, at a time when it was still considered a tall but safe mountain, rather than a volcano at risk of erupting.
Radiocarbon dating of holocene eruptions of the Elbrus volcano (North Caucasus, Russia). O.A.Bogatikov, Doklady Akademii Nauk, 1998, Vol. 363, pp. 219-221; O.A. Bogatikov, I.V. Melekestsev, A.G. Gurbanov, D.M. Katov, A.I. Puriga, Dokl. RAN, 363 (4) (1998), pp. 515-517; Doklady Earth Sciences. V. 363, pp. 1093-1095.
EPR dating and evolution of the Elbrus volcano. D. G. Koshchug, V. M. Gazeev, A. G. Gurbanov, R. V. Shabalin, S. V. Vyatkin. Applied Magnetic Resonance, 2005. vol. 28, pp. 331-342 https://link.springer.com/article/10.1007/BF03166765
Deep Structure and Volcanic Activity of Mount Elbrus and a Portion of the Elbrus–Tyrnyauz Valley: Geological and Geophysical Data. E. A. Rogozhin, A. V. Gorbatikov, Yu. V. Kharazova, M. Yu. Stepanova, and A.V. Nikolaev. Doklady Earth Sciences, 2016, Vol. 471, pp. 1213–1216
The Elbrus Caldera in the Northern Caucasus: Geological structure and time of formation. A. G. Gurbanov, O. A. Bogatikov, I. V. Melekestsev, P. W. Lipman, J. B. Lowenstern, D. R. Miller, and A. Ya. Dokuchaev. Russian Journal of Earth Sciences, 2004, Vol. 6, No. 4.
Ancient earthquake dislocations in the area of Elbrus Volcano, North Caucasus. E. A. Rogozhin, A. G. Gurbanov , A. V. Marakhanov, A. N. Ovsyuchenko, A. V. Spiridonov, and E. E. Burkanov.
Russian Journal of Earth Sciences, 2004, Vol. 6, pp. 293–309,
The Catalogue of Quaternary Volcanoes of the Greater Caucasus Based on Geochronological, Volcanological and IsotopeGeochemical Data. V. A. Lebedeva, G. T. Vashakidzeb. Journal of Volcanology and Seismology, 2014, Vol. 8, pp. 93–107
Contemporary State of the Elbrus Volcanic Center (The Northern Caucasus). Vadim Milyukov, Eugeny Rogozhin,Andrey Gorbatikov,Alexey Mironov,Andrey Myasnikov, Marina Stepanova. Pure Appl. Geophys., 2017, DOI 10.1007/s00024-017-1595-x
Intracanyon basalt lavas of the Debed River (northern Armenia), part of a Pliocene–Pleistocene continental flood basalt province in the South Caucasus. H. Sheth, Kh. Meliksetian H. Gevorgyan, A. Israyelyan, G. Navasardyan. Journal of Volcanology and Geothermal Research, 2015, Vol. 295, pp. 1-15<
Albert, October 2017