Born in Darkness

Clay is not dirt...

One of the most important components of underground landscapes is cave deposits. Dozens of works by karstologists around the world are devoted to their classification. For example, in 1985 R. Tsykin identified 18 genetic types sediments formed in cave environments. Almost all sedimentary and crystalline formations known on the surface are present here, but they are presented in specific forms. Detailed description Cave deposits are a matter for specialists. Our task is to give the reader a general idea of ​​what can be found underground. For this purpose, the classification proposed by D. S. Sokolov and revised by G. A. Maksimovich is more suitable. It includes 8 types of cave deposits: residual, landslide, water mechanical, water chemogenic, cryogenic, organogenic, anthropogenic and hydrothermal.

Residual deposits. Over the course of forty years of cave activity, the author more than once had to accompany groups of non-specialists underground. Their first reaction: “how dirty it is here...” They had to explain that clay is not dirt, but one of the types of sediments that are necessarily present underground.

The history of residual sediments is the history of a drop of water. Karst rocks in small quantities (1-10%) necessarily contain an admixture of sand or clay, consisting of SiO 2, Al 2 O 3, Fe 2 O 3. When limestone or gypsum dissolves, the insoluble residue accumulates on the walls of cracks, slides to the bottom of galleries, and mixes with other cave sediments. Karstologist Yu. I. Shutov calculated that from one cubic meter of Jurassic limestone that makes up the Crimean Mountains (its weight is about 2.7 tons), 140 kg of clay (0.05 m 3) is formed. Studies have shown that it is composed of minerals illite, montmorillonite, kaolinite, feldspar, and quartz. The properties of clays depend on their ratio: some of them swell when moistened, plugging small cracks, while some, on the contrary, easily release water and quickly crumble from the walls. Sometimes bacteria also take part in the formation of clay deposits on the walls: in 1957, the French researcher V. Comartin proved that some types of microbes can obtain carbon directly from limestone (CaCO 3). Thus, worm-shaped or rounded depressions are formed on the walls of caves - clay vermiculations filled with products unsuitable even for bacteria (Fig. 61).

Residual deposits are of no practical importance. The exception, perhaps, is the case when the cave is located near active quarries, where minerals are extracted by explosive means. After strong explosions, equivalent to a local seismic shock of up to magnitude 7, clays can slide off the walls of cracks, temporarily blocking the water supply channels of the springs. There are known cases when their consumption dropped to zero, and then red water began to flow from the sources, carrying suspended clay particles...

In the roar of collapses

In the fundamental summary of G. A. Maksimovich, only 5 lines are devoted to landslide deposits... It was believed that they carry almost no information. Research 60-90 showed that this is not the case. They are divided into three groups of different origins.

Thermogravitational deposits are formed only at the entrance to the cave, where there are large daily and seasonal temperature fluctuations. Their walls are peeling, the vaulted part of the cavity is growing, and crushed stone and fine earth accumulate on its floor. The German speleologist I. Streit, having spent more than ten years and using sophisticated mathematical methods of processing materials, proved that the amount of this material, its composition, size, shape of particles, the number of their edges and faces store encrypted information about climate changes in the area for tens of thousands of years . Based on the spots of these deposits that stand out on the bare slope, Central Asian karst explorers confidently detect subtle entrances to caves from the opposite slope.

Landslide-gravity deposits are formed throughout the caves, but especially abundantly in zones of tectonic fracturing. Crushed stone, debris, small boulders that fell from the vaults give an idea of geological structure high halls, which is difficult to study directly (to study the dome of the Great Hall in the Carlsbad Cave, USA, the American speleologist R. Kerbo even used a hot air balloon!).

Of greatest interest are failure-gravity deposits. The change of prepositions makes a lot of sense: during a collapse, only the material that is in the cave itself accumulates at the bottom of the gallery; when a vault collapses, material from the surface enters it, and when interfloor ceilings collapse, huge halls appear... These deposits are represented by blocks and boulders weighing hundreds of thousands of tons. The sections of caves where they are found present a fantastic sight. Many of them are so unstable that they creak dangerously when a caver climbs on them.

The reddish-brown surface of the limestones is covered with white stars - traces of impacts from fallen stones. A person feels uncomfortable in this chaos. But often here you can find some immediately calming patterns...

In 1989, Simferopol speleologists discovered, and in the 90s they explored and equipped for excursions one of the most beautiful caves in Crimea - Marble on Chatyrdag. In its central part there is the largest collapse hall in Crimea (the area is half football field!), which received the ironic name of the Perestroika Hall in the spirit of the times. To our surprise, order has emerged in the chaos of its blocks: some of them lie horizontally, others are inclined at angles of 30-60°, others are turned upside down, and the stalactites that once grew on them have now turned into “stalagmites”... The secret is that the limestones composing the cave themselves fall at an angle of 30°. Therefore, when a layer is torn off in the vault of the hall, it moves hingedly, with a rotation and even a revolution.

In addition to blocks and boulders, collapse-gravity deposits also include fallen sinter columns. They have been studied better than others in seismic areas - in the Crimea, in the south of France, in the north of Italy. At the same time, it was possible to establish direct and inverse connections between karst science and seismology. Strong earthquakes cause cave vaults to collapse. If the resulting blocks and boulders are difficult to directly associate with them, then oriented fallen columns sometimes confidently indicate the epicenters of earthquakes. Thus, in Crimea, about 60 columns were described lying on a horizontal floor (this is very important, since on inclined floors they can roll away and change orientation). 40% of them gravitate towards the Sudak, 40% - towards the Yalta and 10% - towards the Alushta and Sevastopol epicentral zones. This indicates the migration of sources of strong earthquakes in the Anthropocene from Sudak to Sevastopol. Unfortunately, a calculation scheme has not yet been found to explain the mechanism of displacement of giants with a length of up to 8 m (Monastyr-Chokrak mine), a diameter of up to 3 m (Red Cave) and a weight of up to 70 tons (Mira mine). It is only clear that they were stronger than the earthquakes of the historical period.

When did these earthquakes occur? Here, too, speleology provides seismologists with a reliable dating method. Sinter columns are “mineralogical” plumbs in which the position of the geophysical vertical of a given area is recorded throughout its entire growth. If, after falling, stalactites or stalagmites grow on them (Fig. 62), then by their age, determined by any absolute method (radiocarbon, nuclear magnetic resonance, etc.), the age of the column can be determined (no earlier than...). For Crimea, there are so far only two radiocarbon dates, giving an age of 10 and 60 thousand years for the fallen columns of the Perestroika Hall. In other caves of the world, this range is even wider - from 10 to 500 thousand years...

The feedback between karst and seismology is manifested in the fact that when a cave roof fails, blocks weighing up to 2-3 thousand tons are formed. A blow to the floor when falling from a height of 10-100 m releases energy amounting to 1x10 15 - 10 17 erg, which is comparable to the energy of earthquakes (the Tashkent earthquake of 1966 - 1x10 18 erg). True, it is localized in a small volume of rock, but can cause a noticeable local earthquake with a force of up to 5 points.

Speleological methods for refining seismic zoning maps were widely used in France when determining the locations of nuclear power plants. The same work, which significantly changed the initial ideas of specialists, was carried out in the 90s. in Crimea. This once again proves that in nature everything is interconnected and there are no natural objects that do not carry useful information. You just need to know how to get it.

To finish this topic, let’s briefly touch on one more issue. To what extent are earthquakes dangerous for a caver working underground? Information on this matter is sparse, but it is suggestive. During the Crimean earthquake of 1927, a group from the hydrogeological detachment of P. M. Vasilievsky was in the Emine-Bair-Khosar mine on Chatyrdag. She did not feel the seven-magnitude shock at all, which caused panic among their guides on the surface. On May 1, 1929, during the Germab earthquake (magnitude 9), there were excursionists in the Baharden Cave. They heard a growing roar, individual pebbles fell from the walls, gentle waves began to flow across the lake at their feet... The Vrancea earthquake of March 4, 1977 (8 points) was felt in the Topchika cave (Bulgaria) only by slight fluctuations in the level and temperature of the water in the underground watercourse It would seem clear: even the strongest seismic shocks underground are damped (the phenomenon of “decoupling,” which caused a lot of trouble when the treaty banning nuclear explosions was signed). But let's not rush to conclusions. According to L.I. Maruashvili, during the Baldin earthquake of 1957 it was filled with collapsed rock and ceased to exist as geographical feature Tsipuria karst mine (Georgia). After the earthquake on August 27, 1988, in the Vesennyaya mine (Bzyb massif, Georgia), a blocky dam was displaced at a depth of 200 m. The speleologists who had just climbed out of it survived only by luck. No, earthquakes are no joke - both on the ground and underground...

Spawning moving water

The next notable group of cave deposits is aqueous mechanical deposits. Getting to know them will also not bring much pleasure to a non-specialist. In the Red Cave there are lakes where you plunge almost waist-deep into viscous clay, often leaving the sole of your boot, or even the lower part of your diving suit, in it... But the geologist sees in these deposits a source of various information about the “life” conditions of karst cavities. To obtain them, first of all, it is necessary to study the composition of sediments.

Mineralogical analysis sometimes immediately answers the question of where the water comes from. If the composition of the sediments matches the mineral composition of the host rocks, then the cave was formed by local, autochthonous flows. Therefore, back in 1958, just starting the research of the Red Cave, we already knew that its beginning should be looked for on the plateau of the Dolgorukovsky massif, in the Proval mine - after all, only within the drainage basin that feeds it there are quartz pebbles. While studying the caves of the Koscielska Valley in the Tatras, Polish speleologists noticed that the caves located in the same place, but at different heights above the valley bottom, had different compositions of sand filler: the closer to the bottom, the richer the range of minerals found in it.. A study of the paleogeography of the area showed that this is due to the depth of the river’s incision, which gradually “reached” the catchments of the central part of the Tatras, composed of non-karst rocks.

Of course, with detailed studies, this scheme looks much more complicated. It is necessary to take hundreds of samples, divide them into fractions by size, specific gravity, magnetic and other properties, determine and calculate the content of individual mineral grains under a microscope, etc. The reward is amazing finds. Minerals were unexpectedly discovered in the caves of Crimea: moissanite, cohenite, iocyte, previously known only in meteorites; layers discovered in caves in Bulgaria volcanic ash, which there is reason to associate with the explosion of a volcano on the island of Santorini in the Aegean Sea in the 25th and 4th-1st millennia BC. e.

This is how a thread stretched connecting cave explorers of the 20th century with the problems of Atlantis and the death of the Minoan culture...

The second direction of research into aqueous mechanical deposits is the study of their size. It can be different - from meter-long boulders, sometimes found in caves formed by glacial flows, to the finest clay, the particles of which are micron in size. Naturally, the methods of their research are different: direct measurement, the use of a set of sieves, the use of conventional and ultracentrifuges. What does all this, often lengthy and expensive, work give? The main thing is the restoration of the ancient paleogeographic conditions of the existence of caves. There are connections between the speed of underground flows, the diameter of the channels through which they move, and the sizes of transported particles, which are expressed by rather complex formulas. They are based on the same Bernoulli flow continuity equations, “multiplied” by the equally well-known Stokes equation, which describes the settling rate of particles in stagnant water of different temperatures and densities. The result is a beautiful nomogram proposed by the Czech speleologist R. Burckhardt - a graph by which, knowing the cross-sectional area of ​​the passage and the diameters of the particles deposited at its bottom, one can estimate the average and maximum speed and the flow of the streams that once raged here (Fig. 63).

The study of aqueous mechanical deposits allows us to answer some theoretical problems, in particular the question of in which hydrodynamic zone this cave was founded. In 1942, having discovered thin clay at the bottom of a number of caves in the USA, the experienced geologist and speleologist J. Bretz suggested that they were formed by dissolving limestones by slowly flowing waters: after all, only in them is it possible for the deposition of clay particles! 15 years later, having dug deep pits in dozens of the same caves, karst expert Davis established that rich clays only crown a very complex multi-meter section of the filler. Under the clays there were layers of sand and gravel, brought by a powerful stream, then followed by a sinter crust, which could only have formed during long-term drainage of the cave, below - clay again appeared in the section, lying on the boulders... This is how water-based mechanical deposits help specialists “read” the history development of caves.

“Upper drop” and “bottom drop”

The terms “stalactite” and “stalagmite” (from the Greek “stalagma” - drop) were introduced into literature in 1655 by the Danish naturalist Olao Worm. A hundred years later, a no less figurative definition by Mikhail Lomonosov appeared in Russian literature: “drip”... Indeed, these formations are associated with the droplet form of water movement. We already know some features of the behavior of a drop as a liquid. But this is not just water, but a solution containing certain components. When a drop of solution forms at the base of a water-filled crack, it is not only a struggle between surface tension and gravity. At the same time, chemical processes begin, leading to the precipitation of microscopic particles of calcium carbonate at the contact between the solution and the rock. Several thousand drops falling from the ceiling of the cave leave behind a thin translucent ring of calcite at the rock/solution contact. The next portions of water will already form drops at the calcite/solution contact. This is how an ever-lengthening tube is formed from the ring. The longest tubes (brčki) are 4-5 m (Gombásek cave, Slovakia). It would seem that the chemical essence of the process is simple - a reversible reaction

CaCO 3 + H 2 O + CO 2 Ca 2+ + 2HCO - 3. (1)

When limestone dissolves, the reaction proceeds to the right, with the formation of one divalent Ca ion and two monovalent HCO 3 ions. When deposits form, the reaction goes to the left and the mineral calcite is formed from these ions. But there is a “pitfall” here too, and not just one...

In many textbooks on geography and geology, the formation of stalactites is explained by the evaporation of water. A.E. Fersman did not avoid this mistake in his early works. But we already know that in caves the deficit of air saturation with moisture is close to 0. In such conditions, condensation rather than evaporation predominates.

Reaction (1) actually occurs in several stages. First, water interacts with carbon dioxide:

H 2 O + CO 2 = H 2 CO 3 H + + HCO - 3. (2)

But carbonic acid is weak and therefore dissociates into a hydrogen ion (H +) and an HCO - 3 ion. The hydrogen ion acidifies the solution, and only after this does the dissolution of calcite begin. This means that in formula (1) only one HCO 3 ion comes from the rock, and the second is not associated with it and is formed from water and carbon dioxide introduced into the karst massif. This reduces the estimated activity of the karst process by 20-30%. Let's look at just one simple example. Let the sum of all ions in water be 400 mg/l (including 200 mg/l HCO 3). If we use analysis to evaluate drinking water, then all 400 mg/l are included in the calculation (we don’t care where the individual components in the water came from, what’s important is that they are there). But if the intensity of the karst process is calculated from this analysis, then the sum of ions minus half the content of the HCO 3 ion (400-100 = 300 mg/l) should be included in the calculation. Such errors in calculations are found in the works of many karstologists around the world, including those with high scientific degrees and titles.

Then it is necessary to estimate what difference in partial pressures of CO 2 there is in the system. In the 40-50s. it was believed that the karst process occurs only due to CO 2 coming from the atmosphere. But in the air globe it is only 0.03-0.04 volume % (pressure 0.0003-0.0004 mm Hg), and fluctuations in this value across latitude and altitude above sea level are insignificant. Meanwhile, it has long been noticed that the caves of temperate latitudes and subtropics are richer in deposits, while in the caves of high latitudes and high altitudes there are very few of them... A study of the composition of soil air, carried out by a group of Hungarian speleologist Laszlo Jakuch, showed that the CO 2 content in it 1-5 volume %, that is, 1.5-2 orders of magnitude more than in the atmosphere. A hypothesis immediately arose: stalactites are formed by a difference in the partial pressure of CO 2 in cracks (the same as in soil air) and the air of caves, which has an atmospheric CO 2 content. The last adjustment was made by the direct determination of CO 2 in the air of the caves. The final “diagnosis” says: stalactites are formed mainly not by the evaporation of moisture, but in the presence of a partial pressure gradient of CO 2 from 1-5% (soil air and water in cracks) to 0.1-0.5% (air in caves) .

While the feeding channel of the stalactite is open, drops regularly flow through it. Breaking off from its tip, they form a single stalagmite on the floor. This happens quite slowly (tens - hundreds of years), and therefore such forms reaching out to each other in many equipped caves of the world received the figurative name of “eternal lovers”. When the feeding channel becomes overgrown, clogged with clay or grains of sand, one of the lovers will have a “heart attack” - an increase in hydrostatic pressure in the channel. Its wall breaks through, and the stalactite continues to grow due to the flow of a film of solutions along its outer side (Fig. 64). If water seeps out along bedding planes and inclined cracks in the vault, rows of stalactites, fringes and curtains of the most bizarre shapes and sizes appear.

Depending on the constancy of the water inflow and the height of the hall, single stalagmites-sticks with a height of 1-2 m and a diameter of 3-4 cm are formed under the drips; “flattened”, similar to the stumps of cut trees, or cone-shaped, reminiscent of towers or pagodas. These are the largest sinter formations of caves, measuring several tens of meters in size. The tallest stalagmite in the world is now considered to be a 63-meter giant in the Las Villas cave (Cuba), and in Europe - a 35.6-meter one, in the Buzgo cave in Slovakia. When stalactites and stalagmites grow together, stalagnates are formed, gradually turning into columns. Some of them reach 30-40 m (height) and 10-12 m (diameter). When flowing down in the form of films and flat streams, cascading deposits of various shapes and sizes are formed.

In addition to the listed widespread forms, in subaerial conditions (that is, in the air), all sorts of bizarre formations are formed that resemble flowers (anthodites), bubbles (blisters, balloons), corals (coralloids, popcorn, botryoids), spirals (helictites), etc. The greatest Helictites surprise both ordinary visitors and specialists. The largest of them, 2 m long, were described in Jaul Cave (South Africa). A spiral gypsum helictite "Spring" 80 cm long has been described in New Zealand (Flour Cave). Huge gypsum “paws” 5-7 m long were described in the caves of Cap Coutan (Turkmenistan) and Lechugia (USA). The mechanism of formation of such forms has not been fully understood; mineralogists from many countries are studying them. IN last years a new aerosol hypothesis for the formation of some subaerial forms arose. This creates a bridge between the study of condensation and ionization of air and the problems of speleogenesis.

Subaquatic forms are no less diverse. A thin mineral film forms on the surface of underground lakes, which can attach to the wall of the bath or to a stalactite that has reached the water level, turning into a thin plate. If the water level in the bath fluctuates, then several levels of growth are formed, reminiscent of lace trims. In weakly flowing baths and channels underground rivers sinter dams are formed, ranging in height from a few centimeters to 15 m (Los Brijos, Brazil). At the bottom of the baths or in micro-recesses in the body of the sag, cave pearls often form, just like real pearls, consisting of dozens of growth concentrates. An amazing formation stands out - “moon milk”. Under different conditions, it can be semi-liquid, creamy, dense like cottage cheese, free-flowing like flour. When dried, moon milk turns into fine white dust, and a speleologist climbing out of a narrow vertical chimney-chimney looks like an “anti-chimney sweep.” Moon milk has about a hundred synonyms; its formation is “explained” by more than 30 hypotheses. There is no single theory yet, just as there is probably no single form of “moon milk” - it is polygenetic...

As the famous Russian mineralogist D.P. Grigoriev (St. Petersburg) and one of the best diagnosticians of cave minerals in the world, V.I. Stepanov (Moscow), pointed out, the variety of forms of cave deposits is explained by the peculiarities of their ontogenesis: origin, selective growth and secondary changes. In this direction, caves open up the broadest opportunities for the crystallographer and mineralogist, just to preserve the sinter decoration until their arrival... Unfortunately, research into the subtleties of mineralogy and geochemistry of caves is still the lot of amateurs. These labor-intensive works do not find a customer - the sinter deposits of caves, determining their external beauty, are basically of no importance in practice.

Since the 70s XX century the situation began to slowly change: through the external exoticism of forms, internal patterns that had not only mineralogical interest began to shine through more and more noticeably. Let's give just a few examples. In 1970, G. A. Maksimovich, summarizing scattered data from many caves around the world, proved that carbonate deposits of different morphologies and sizes are formed at different intensities of water inflow. Thus, cover deposits and dams are formed at a water flow rate of 1-0.01 l/s; cone-shaped stalactites from 0.0005 to 0.00001 l/s; eccentric forms - less than 0.000001 l/s. The brilliant foresight of the Russian mineralogists N.P. Chirvinsky and A.E. Fersman about the importance of oriented growth of minerals has now been expanded into a harmonious concept of natural plumbs and levels. In the 80s it was brilliantly used to reconstruct recent tectonic movements in the karst regions of Italy and France in connection with the construction of nuclear power plants. The annual cycles of stalactites and stalagmites, clearly visible in Fig. 64 turned out to be only a special case of the manifestation of cosmic rhythms.

In the talented book of geologist and speleologist Vladimir Maltsev “Cave of Dreams. Cave of Fate”, Astrel Publishing House, 1997, an entire chapter is devoted to the mineralogy of one of the most beautiful caves in the world - Cap-Coutan in Turkmenistan. The paradoxical title (“The Science of Amateurs”) did not prevent the author from talking popularly, but at the same time quite professionally, about modern ideas about the formation of many mineral formations in caves - from the simplest stalactite to the mysterious eccentric.

The chemical composition of aqueous chemogenic deposits is also very interesting. A.E. Fersman at the beginning of the 20th century. wrote that traditional ideas about calcite as the main mineral of caves are only partly correct. In the 80s The fundamental summary of the charming American mineralogist Carol Hill and the temperamental Italian speleologist Paolo Forti /36/ provides data on 186 minerals of the world’s caves. In first place in terms of the number of mineral species (numerator) are ore minerals. According to the number of forms in which they crystallize (denominator) - carbonates. In total, minerals of 10 classes were found underground: ore - 59/7; phosphates - 34/4; minerals of different classes - 28/6; oxides - 12/19; silicates - 11/14; carbonates - 10/27; sulfates - 10/16; nitrates - 6/4; chlorides - 4/9; hydroxides - 4/3. A. E. Fersman’s prediction about the formation of cave minerals in different geochemical environments was also confirmed. Obviously, not all of them have been identified and characterized. In particular, the study of the mineralogy of thermal caves is just beginning (Fig. 65).

Ice Kingdom

Aqueous chemogenic deposits are the product of liquid and vapor water. Water in the form of snow and ice is typical for caves where negative air temperatures are constantly or seasonally observed.

Snow accumulations form only in underground cavities with large entrances. Snow flies into the cave or accumulates on the ledges of the mines, falling down in small avalanches. There are known cases of the formation of underground snow cones with a volume of tens to hundreds of cubic meters at a depth of 100-150 m under the inlet (Crimea, Bezdonnaya, Fig. 19). One of the largest accumulations of snow is described in the Snezhnaya mine (Georgia). Initially, the snow enters the entrance funnel with a depth of 40 m and an area of ​​2000 m2 along the upper edge. From here it enters a 130-meter shaft with a width of 2 to 12 m (transit area). Through a hole in its bottom it falls to a depth of 200 m, in Big hall, where it forms a cone with an area of ​​about 5 thousand m2 and a volume of more than 50 thousand m3. IN different years its configuration changes, as snow-ice plugs or rounded thawed patches form in the snow - rain runoff channels that change the paths of snow flow from the surface.

Ice in caves has different genesis. Most often, snow compacts, which first turns into firn and then into glacier ice; less often, this ice even begins to move, forming an underground glacier (Argentiere, France); finally, the preservation of ice formed in permafrost conditions in caves is very rarely observed (Surprise, Russia), or the flow of land glaciers (Castelgarde, Canada). Second path of education cave ice- ingress of melted snow water into cold (static) caves (Buzluk, Ukraine). The third way is air cooling in wind (dynamic) caves (Eisriesenwelt, Austria), and the fourth is the formation of sublimation crystals of atmospheric origin on a cooled rock surface or on ice. It is interesting that ice of different genesis has different mineralization: the most “fresh” (only 30-60 mg/l) is sublimation and glacier ice, the most “salty” is ice from gypsum and salt caves (2 or more g/l). A special case is ice caves formed directly in the ice of mountain or cover glaciers. Their ice secondary formations are associated with the melting and freezing of the host ice (Aimfjomet, Norway, etc.)

Ice caves are most often found in the mountains, at an altitude of 900 to 2000 m. One of the most famous is Eisriesenwelt in Austria. The entrance to it is located at an altitude of 1656 m; ice covers the bottom of the entrance gallery at a distance of up to 1 km, occupying an area of ​​20-30 thousand m2 in different years. One of the largest glacier caves is Dobshinska (Slovakia). On an area of ​​12 thousand m2, more than 145 thousand m3 of ice have accumulated here, forming powerful cascades (the age of the ice in their lower layers is up to 7 thousand years) and ice deposits (age 1-2 years). In Russia the most famous is Kungurskaya ice cave. Accumulations of ice form in it in winter period and only in the entrance area. The volume of ice formed depends on weather conditions cold period and from the number of visitors to the cave.

Being the simplest mineral compound from the group of oxides, ice forms all the forms characteristic of ordinary sag. More often than others there are “frozen waterfalls” - cascades up to 100 m high (Eisriesenwelt), stalactites, stalagmites, columns 10-12 m high, various draperies; less commonly, ice helictites up to 10 cm long and transparent hexagonal crystals forming aggregates up to 60 cm in diameter. It happens that underground lakes also freeze, the smooth surface ice of which is sometimes covered from below by complex underwater forms of growth (caves of the Pinego-Kuloi region and Siberia).

9.6. For fertilizers - underground

Various organogenic deposits often accumulate in caves: guano, bone breccia, phosphorites, saltpeter, which are an excellent fertilizer.

The most widespread deposits of guano are bat or bird droppings. In mid-latitudes it rarely forms industrial concentrations. Usually these are thin layers or cone-shaped heaps 1-2 m high and 2-5 m in diameter, formed under the attachment sites of small (tens - hundreds of individuals) colonies of bats. In the lower latitudes of all continents, bats form huge colonies, reaching 10-25 million individuals (Brackenskaya, Novaya, USA). In such caves, as well as in cavities where birds nest, accumulations of guano reach 40 m in thickness (Kirkulo, Cuba), and reserves reach 100 thousand tons (Carlsbad, Mamontova, USA). In a number of caves in the Northern and South America guano reserves have been completely depleted; in Cuba it is still considered “black gold”. In the Kirkulo cave, up to 1000 tons of guano are mined annually, and its reserves are estimated at 80 thousand tons. The cost of industrial guano extraction is only 15% of its selling price. In Thailand, income from the exploitation of several “guan” caves reaches 50 thousand dollars. With this money there are several Buddhist temples and community schools.

Guano is a valuable fertilizer. It contains from 12 to 30% phosphorus, nitrogen, and potassium compounds. Guano fertilizers - concentrate. To use it without damaging the root system of plants, you need to “dilute” it with black soil in a ratio of 1:5, 1:10. Cave guano deposits are also exploited in Venezuela, Malaysia, and Kenya. Locals it is used in subsidiary farming in many karst regions of the world (France, Spain, Italy, Slovenia, Greece, Uzbekistan, Vietnam, Australia, etc.). In recent decades, due to the “champignon boom” in France, guano has been used in growing mushrooms.

In caves where there is guano, the phosphorus and sulfur contained in it give rise to acid solutions that interact with bedrock and sediments. As a result, corrosive forms arise - “guan” pots, domes, niches, as well as a whole spectrum (more than 50!) of still poorly studied phosphate minerals. In caves where the formation of guano continues to this day, it is very rich and specific animal world, many of whose representatives are carriers of diseases. In the 60-80s. While exploring caves at low latitudes, many European speleologists became seriously ill; they were very susceptible to “tropical” viruses. Nowadays, near caves with guano there is a warning sign: “Danger: histoplasmosis.”

Somewhat less frequently, phosphorus-containing deposits form in caves rich in vertebrate bone remains. In Europe, the bone-bearing caves of Drachenhele and Michnitz (Austria) and Quercy (France) are especially well studied. Phosphorus-containing deposits are loose sandy-clayey and earthy red-brown rocks rich in phosphorus oxide (22-25%), silica (22-27%), aluminum and iron (2-5%). Bone breccias are often cemented by carbonate deposits. In a number of caves in Belgium, France, and China, breccias containing bone remains of vertebrates are completely mined for industrial needs.

Accumulations of biogenic nitrate (NaNO 3) are occasionally found in caves that served as shelter for wild animals or pens for livestock. In many caves in the states of Kentucky (Mamontova), South Virginia (Sinnet), Indiana (Wyandot), Georgia (Kingston) in the USA, the foothills of the Crimea and the Caucasus in the 19th century. saltpeter was mined for the production of gunpowder. In particular, a small powder factory using “cave raw materials” operated in Sevastopol during the Anglo-Franco-Russian War of 1854-1855. Interestingly, the presence of nitrate rosettes on the walls is evidence of the relatively low (only 70-80%) air humidity in the caves.

Strictly speaking, anthropogenic deposits associated with human presence underground also belong to organogenic sediments. They have a number of features, and so we will look at them below.

Hot solution deposits

In the section “Secrets of the Underground Spheres” we talked about how hydrothermal caves were discovered. A number of common and specific minerals were discovered in them, the total amount of which was rapidly increasing and by the end of the 90s. exceeded 30. In a number of cases, the temperature of formation of hydrothermal minerals was confirmed by the inclusion homogenization method. Sometimes the finds of certain minerals are a “signal” about the possibility of the formation of a cave by hot solutions. Among them are anhydrite (Diana, Romania), ankerite (cavities opened by coal mines of Donbass, Ukraine), aragonite (Zbrasovskaya, Czech Republic, a number of caves Central Asia), barite (Baritovaya, Kyrgyzstan), hematite (Wind, USA), quartz, cinnabar, rutile (Magian, Tajikistan), etc. A. E. Fersman also classified some varieties of zonal calcite deposits as hydrothermal formations - marble onyxes, in pursuit behind which the sintered decoration of many beautiful caves was destroyed...

Hydrothermal formations have not only a specific composition, but also forms of release. Among them there are often well-cut crystals, single crystals or crystals growing on each other (Iceland spar from Crimean caves). I. Kunski described “geysermites” growing when hydrothermal solutions enter from below. And according to one hypothesis, the formation of intersecting partitions - boxwork - on the walls of Wind Cave (USA) is associated with hydrothermal solutions.

The study of hydrothermal minerals links speleology with the study of mineral deposits. Karst deposits of lead and zinc, antimony and mercury, uranium and gold, barium and celestine, Iceland spar and bauxite, nickel and manganese, iron and sulfur, malachite and diamonds are known /17/. This is a special, very complex topic that requires special consideration.

9.8. Colors of the Underworld

The first attempt to connect the nature of minerals with their color was made by A.E. Fersman. Working mainly in carbonate karst caves, he noticed their light colors - from white ice caves of Crimea to the yellow and brick-red deposits of Tyuya-Muyun.

60 years after the work of Alexander Evgenievich, we know a lot more about the color of cave minerals. It depends on the presence of metal ions, the degree of oxidation and hydration of their compounds, the presence of mechanical impurities and organic material /36/. Iron and its oxides determine the red, orange and yellow, brown and fawn color of minerals; manganese - blue; copper - green, blue (blue-green), gray-yellow; nickel - pale green and lemon yellow; admixture of clay - red, orange-brown and yellow-brown; organic substances, bat guano, humic fulvic acids - red, orange, yellow, blue, red-brown, brown, amber color. Achromatic tones (white, light gray, grey) have ice and a number of minerals containing an admixture of manganese.

All these colors are distributed differently on the surface of the deposits, forming clear layers or outlining bizarre contours that defy gravity. The “texture” of the surface plays a big role in the perception of color. Bedrock looks completely different when it is freshly fractured or covered with a thin ferromanganese crust, dry and moistened with water.

Skillful polishing, which reveals their internal structure, gives the drips a special charm (Fig. 64). Finally, the strength of light and the nature of lighting play a significant role. One thing is to examine the cave by the light of a stearine candle; another - with torches; the third - with electric lighting. In this regard, caves are as changeable as Proteus...

Changes color and ice. Covering the walls of wells with a thin layer, it is almost colorless, and the color of the stone or sinter “comes through” through it. The thicker the layer of ice, the less transparent it is and gradually acquires its own bluish-white or white tint.

In the Silice Cave (Slovakia), red-colored ice deposits are known (due to the admixture of clay particles). If water freezes slowly, the ice is more transparent; if it’s fast, then the compressed air bubbles determine the milky tint of the ice...

The color of walls and sagging largely determines a person’s sensations. Often the coloring warns: “be careful! there has been a fresh collapse here”; “here is a flood zone during a flood”; "here - stones are falling" ...

Sudden changes in the color scheme of caves are alarming and create an elevated or, on the contrary, depressing mood. It’s not without reason that some of them (Aptelek, Hungary) host color music concerts.

We have already talked above about the fluorescence of deposits. The color of their glow is usually orange-red, pale green, yellow-green, bluish-green, pale blue, violet-blue, violet. It is associated with the presence of microimpurities of copper, zinc, strontium, and manganese. The presence of iron ions, on the contrary, “quenches” the glow. Why does this happen? Energy is emitted and absorbed in portions - quanta. When an atom of a substance absorbs a quantum of light, its electron “jumps” to a higher energy level - an orbit further away from the nucleus. But such an excited state is unstable: electrons tend to occupy a position where their energy is lowest. Therefore, sooner or later this atom returns to its normal state, “breaking down” to its previous level and returning the energy difference in the form of a light quantum. The time an electron spends in an excited state is the duration of the afterglow. In caves it is abnormally high and reaches 2-6 seconds (usually about 0.015 seconds...). The reason for this phenomenon has not yet been clarified, but this does not prevent us from admiring the deposits, which at first seem to be filled from within with a cool colored fire, which outlines their bizarre outlines and slowly fades...

Residual. If the insoluble part of the carbonate rock (clay and sandy particles) is not carried away water streams, but remains at the place of its formation (the so-called “glinka”), then this is eluvium.

Landslide-gravity. Landfalls. Blocks, crushed stone.

River sediments - alluvium, alluvial. Sand, pebbles, gravel.

Cryogenic. Products of glacial activity. In the lower parts of nival-corrosion wells. Debris of different sizes.

Biogenic. Guano (tropical caves), bat excrement, in the entrance parts - bones of fallen animals, tree trunks.

Chemogenic.

All types of sinter formations:

a).Stalactites, stalagmites, stalagnates (stalactite and stalagmite fused into a column), wall cladding, curtains, curtains (if the source of the solution is not a point, but a linear one - a gap), sticks, pagodas, jellyfish, columns, stone dams, stone waterfalls. All listed forms have the same origin.

b).Pasta. If the stalactite has an icicle-shaped, conical shape, then the pasta has approximately the same thickness along its entire length (up to a meter or more). The grains of the calcite composing it are larger, the hollow channel in the pasta has a diameter of up to several mm, while in the stalactite it is very thin. The stalagmite has no channel at all.

c).Corallites (in the West they are called botryoids). The mechanism of their formation is not completely clear. They are probably formed by the diffusion of ions from surrounding rocks through water films condensing on the walls of the cavities. They usually form on the side walls and bottom of caves.

d).Crystallictites. Bundles of well-defined calcite crystals (up to the first cm) growing from the tops of corallites.

d).Helictites. From the Greek word "helicos" - twisted. Stalactite grows strictly vertically, since its growth is controlled by gravity. The growth of helictite is controlled not by gravity, but by crystallization force. A crystal consists of parallel rows of atoms and the next row adjusts to the previous one. Thus, growth occurs along the crystal growth axis, which can be oriented in space as desired.
Therefore, the direction of helictite growth is also independent of gravity. Twisting occurs due to impurities of other atoms. If a foreign atom appears in a layer of identical atoms, then the next layer will not be parallel to the previous one, and the direction of crystal growth will change. Helictite is an intergrowth of parallel hair-like crystals of calcite or aragonite.

e).Moonmilk. A fine, moist mass, similar to wet tooth powder. It represents nuclei of calcite crystals, the growth of which was blocked by the adsorption of magnesium ions by the surface of the nuclei.
Therefore, already formed microcrystals do not grow further. But the solution is supersaturated with calcium carbonate and the latter must precipitate. More and more new crystals fall out, the growth of which is immediately blocked.

g).Antholites. Needle-shaped crystals of easily soluble minerals (gypsum, etc.) at the bottom of dried puddles and lakes. Typical for southern, tropical caves, where humidity is not high and drying out is possible. In the Caucasus, they are sometimes found at significant depths, where the temperature can increase by 5-10 degrees. On average, the temperature of the rocks increases by 1 degree for every 33 m of depth. They say: the geothermal gradient is 1 degree/33 m.

h).Pisoliths (cave pearls). Unattached shape, round formations up to 1-2 cm. in diameter at the bottom of underground lakes.

e).Films, reserves, rims, saucers - all this is along the shores of underground lakes.

3. CAVE DEPOSITS

The caves contain almost all sedimentary and crystalline formations known on the surface, but they are presented in specific forms.

1. Residual deposits. Karst rocks necessarily contain in small quantities (1–10%) an admixture of sand or clay, consisting of SiO 2, Al 2 O 3, Fe 2 O 3. When limestone or gypsum dissolves, the insoluble residue accumulates on the walls of cracks and slides to the bottom of the galleries. Mixes with other cave sediments. For example, from 1 m³ of Jurassic limestone (about 2.7 tons) 140 kg of clay is formed, which is composed of the minerals illite, montmorillonite, kaolinite, feldspar, and quartz. The properties of clays depend on their ratio: some of them swell when moistened, plugging small cracks, while some, on the contrary, easily release water and quickly crumble from the walls. Sometimes bacteria also take part in the formation of clay deposits: some types of microbes are able to obtain carbon directly from limestone - this is how worm-shaped or rounded depressions (“clay vermiculations”) are formed on the walls.

2. Landslide deposits are divided into three groups of different origins.

– thermogravitational ones are formed only at the entrance to the cave, where daily and seasonal temperature fluctuations are large. Their walls are “peeling”, the vault part of the cavity is growing, and crushed stone and fine earth are accumulating on the floor. The amount of this material, its composition, size, shape of particles, the number of their edges and faces store encrypted information about climate changes in the area for tens of thousands of years.

– landslide-gravity deposits are formed throughout the caves, especially abundantly in zones of tectonic fracturing. Crushed stone, debris, small boulders that fell from the vaults give an idea of ​​the geological structure of the halls, which is difficult to study directly.

– collapse-gravity deposits: during a collapse at the bottom of the gallery, only the material that is available in the cave itself; when the vault collapses, material from the surface enters it, and when the interfloor ceilings collapse, huge halls appear. These deposits are represented by blocks and blocks weighing hundreds of thousands of tons. The reddish-brown surface of the limestones is covered with white “stars” - traces of impacts from fallen stones. The limestones composing the cave themselves fall at an angle of 30º, so when a layer in the vault of the hall is torn off, it moves hingedly, with rotation and inversion. In addition to blocks and boulders, fallen sinter columns are observed. Strong earthquakes cause the collapse of vaults, and oriented fallen columns sometimes confidently point to the epicenters. Sinter columns are also “mineralogical” plumbs, in which the position of the geophysical vertical of a given area is recorded throughout its entire growth. If, after falling, stalagmites or stalactites grow on them, then by their age the age of the column can be determined.

The feedback between karst and seismology is that when a cave roof fails, blocks weighing up to 2-3 thousand tons are formed. Hitting the floor when falling from a height of 10–100 m releases energy equal to 1·! 0 13 – 10 15 erg, which is comparable to the energy of earthquakes. It is localized in a small volume of rock, but can cause a noticeable local earthquake with a magnitude of up to 5 points.

3. Water mechanical deposits are a source of information about the conditions for the development of karst cavities. If the composition of the sediments matches the mineral composition of the host rocks, then the cave was formed by local flows. The size of such deposits ranges from meter-long boulders (in caves formed by glaciers) to the finest clay. Knowing the cross-sectional area of ​​the passage and the diameters of deposited particles, they estimate the speed and flow rate of ancient flows and in which hydrodynamic zone the cave was founded.

4. aqueous chemogenic deposits. The terms “stalactite” and “stalagmite” (from the Greek “stalagma” - drop) were introduced into literature in 1655 by the Danish naturalist Olao Worm. These formations are associated with the droplet form of movement of water - a solution containing various components. When a drop of solution forms at the base of a water-filled crack, it is not only a struggle between surface tension and gravity. At the same time, chemical processes begin, leading to the precipitation of microscopic particles of calcium carbonate at the contact between the solution and the rock. Several thousand drops falling from the ceiling of the cave leave behind a thin translucent ring of calcite at the rock/solution contact. The next portions of water will already form drops at the calcite/solution contact. This is how an ever-lengthening tube is formed from a ring (brčki - reach 4–5 m in the Gombásek cave, Slovakia). Thus, the chemical basis of the process is a reversible reaction

CaCO 3 + H 2 O + CO 2<=>Ca 2+ + 2HCO 3 - (1)

When limestone dissolves, the reaction proceeds to the right, producing one divalent Ca ion and two monovalent HCO 3 ions. When deposits form, the reaction goes to the left and the mineral calcite is formed from these ions. Reaction (1) occurs in several stages. First, water reacts with carbon dioxide:

H 2 O + CO 2 = H 2 CO 3<=>H + + HCO 3 - (2)

But carbonic acid is weak, therefore it dissociates into the hydrogen ion H + and the HCO 3 - ion. The hydrogen ion acidifies the solution, and only after this does the dissolution of calcite begin. In formula (1), only one HCO 3 ion comes from the rock, and the second is not associated with it and is formed from water and carbon dioxide introduced into the karst massif. This reduces the estimated activity of the karst process by 20–20%. For example, let the sum of all ions in water be 400 mg/l (including 200 mg/l HCO 3). If we use an analysis to evaluate drinking water, then all 400 mg/l are included in the calculation, but if we calculate the intensity of the karst process using this analysis, then the sum of ions minus half the content of the HCO 3 ion should be included in the calculation (400–100 = 300 mg/ l). It is also necessary to take into account what partial pressure difference of CO 2 there is in the system. In the 40s–50s. it was believed that the karst process occurs only due to CO 2 coming from the atmosphere. But in the air it is only 0.03–0.04% by volume (pressure 0.0003–0.0004 mm Hg), and fluctuations in this value across latitude and altitude above sea level are insignificant. But it has been noticed that the caves of temperate latitudes and subtropics are richer in deposits, while in the caves of high latitudes and high altitudes there are very few of them. A study of the composition of soil air showed that the CO 2 content in it is 1–5 vol.%, i.e. 1.5–2 orders of magnitude more than in the atmosphere. A hypothesis immediately arose: stalactites are formed by a difference in the partial pressure of CO 2 in cracks (the same as in soil air) and cave air, which has an atmospheric CO 2 content. Thus, stalactites are formed mainly not by the evaporation of moisture, but in the presence of a partial pressure gradient of CO 2 from 1–5% to 0.1–0.5% (air in caves). While the feeding channel of the stalactite is open, drops regularly flow through it. Breaking off from its tip, they form a single stalagmite on the floor. This has been happening for tens or hundreds of years. When the supply channel becomes overgrown, clogged with clay or grains of sand, the hydrostatic pressure in it increases. The wall breaks through, and the stalactite continues to grow due to the flow of a film of solutions along the outside. When water seeps along bedding planes and inclined cracks in the vault, rows of stalactites, fringes, curtains, and cascades appear. Depending on the constancy of the water inflow and the height of the hall, single stalagmites-sticks with a height of 1–2 m (up to tens of meters) and a diameter of 3–4 cm are formed under the drips. When stalactites and stalagmites grow together, columns are formed - stalagnates, up to 30–40 m in height and in diameter 10–12 m. In subaerial conditions (air), anthodites (flowers), bubbles (balloons), corals (coralloids, botryoids), helictites (spirals up to 2 m high), etc. are formed. Subaqueous forms are noted. A thin mineral film forms on the surface of underground lakes, which can attach to the wall. If the water level fluctuates, build-up levels are formed. In weakly flowing water, dams-gurs (from a few cm to 15 m high) and cave pearls are formed. The origin of only “moon milk” is still inexplicable.

Rice. 10. Geochemical conditions for the formation of aqueous chemogenic deposits in caves. Rocks and sediments: a – limestone, b – dolomite, c-gypsum, d – rock salt, d – ore body, f – clay, g – guano, h – soil; waters: i – soil, k – infiltration, l – thermal; m – classes of minerals (1 – ice, 2 – sulfates, 3 – nitrates, 4 – halogens, 5 – phosphates, 6 – sulfur, 7 – carbonates, 8 – oxides, 9 – carbonate metals, 10 – sulfides); n – special conditions formations (presence of: 1 – pyrite, 2 – bacteria, 3 – bat colonies, 4 – hydrothermal solutions, 5 – pyrite and marcasite); o - mineral species and forms of their isolation (1 - ice stalactites; 2 - dendrites of epsomite, mirabilite, thenardite; 3 - epsomite and mirabilite crusts; 4 - crystals of gypsum, barite, celestine; 5 - various calcite formations; 6 - moon milk; 7 – salt forms; 8 – hydrocalcite; 9 – aluminum phosphates; 10 – nitrophosphates; 11 – zinc and iron minerals; 12 – sulfide oxides; 13 – vanadinite, fluorite; 14 – iron and lead oxides; 15 – limonite, goethite; 16 – cerussite, azurite, malachite; 17 – opal stalactites; 18 – hemimorphite; 19 – quartz crystals)

5. Cryogenic. Water in the form of snow and ice is typical for caves with negative temperatures. Snow accumulations form only in underground cavities with large entrances. Snow flies into the cave or accumulates on the ledges of the mines. Sometimes snow cones with a volume of tens to hundreds of m³ are formed at a depth of 100–150 m below the inlet. Ice in caves has different genesis. More often, snow compacts and turns into firn and glacier ice. It is less common for an underground glacier to form, and even less often the preservation of ice formed in permafrost conditions or the flow of land glaciers is noted. The second way of ice formation is the entry of melted snow water into cold (static) caves. The third way is cooling the air in wind (dynamic) caves and the fourth is the formation of sublimation crystals of atmospheric origin on a cooled rock surface or on ice. The least mineralized (30–60 g/l) is sublimation and glacier ice, the most (more than 2 g/l) is ice from gypsum and salt caves. Ice caves are most often found in the mountains, at an altitude of 900 to 2000 m. Ice forms all the forms characteristic of ordinary deposits.

6. Organogenic: guano, bone breccia, phosphorites, saltpeter. Anthropogenic deposits are also identified.

7. Hydrothermal: anhydrite, aragonite, ankerite, barite, hematite, quartz, cinnabar, rutile. Also, some varieties of zonal calcite deposits are marble onyxes. Such formations have specific forms of release: often well-cut crystals, intersecting partitions (boxworks), “geysermites”... Karst deposits of lead and zinc, antimony and mercury, uranium and gold, barium and celestine, Iceland spar and bauxite, nickel and manganese are known, iron and sulfur, malachite and diamonds.

Conclusion

Karst is very widespread on the surface of the Earth and in the near-surface zone of the earth's crust. There is exceptionally great specificity and versatility of karst forms and hydrological phenomena. In most cases, the bathtub topography predominates on the surface of the Earth, with the exception of remnant tropical karst (which in itself is universal), but even in the tropics on the plains, bathtub relief is quite widespread, and it is often combined with remnant relief. Karrs are not found in all types of karst, but as soon as the karst rock is exposed on the surface, they appear. In different geological-geomorphological and physical-geographical conditions, karst forms are represented by different varieties, but the main types of forms and hydrological phenomena are evident everywhere. The universality of karst forms and hydrological phenomena is a consequence of the leading process in the formation of karst: the process of leaching of soluble rocks. We can emphasize the priority of the geological basis in the development of karst, karst relief and karst landscape. The development of karst is also influenced by the physical-geographical situation, which is associated with the latitudinal and altitudinal zonation of karst phenomena. Karst relief, karst landscapes and the processes occurring in them are so specific that not a single serious economic activity in a karst territory can be carried out without taking them into account and often without special study. Karst has a profound impact on the landscape as a physical-geographical complex. It affects runoff, karst landforms - on the microclimate and distribution of soil and vegetation cover, karst rocks and their composition - on soils and vegetation, the chemical composition of karst waters, on the landscape as a whole, etc. The drainage capacity of karst increases the lack of moisture in arid areas and, conversely, creates more favorable conditions for the development of landscapes in areas that are overly moist. Karst leads to permafrost degradation, also significantly improving natural features territories. The degree of influence of karst on the geographical landscape can be judged based on the morphological and genetic type of karst.

Features of karst, often its morphological-genetic type and classification rank of the geographical landscape of the karst territory. The following taxonomic system for karst zoning can be proposed: karst country - region - province - district - district. Within the region, during a detailed study, it is recommended to identify typological units (areas of different types of karst), however...

PROCESSES As a result of karst-suffusion processes and phenomena, the stability of the geological environment decreases, which leads to catastrophic consequences (subsidence, failures, deformation of structures). In the Russian Federation, karst processes are widely developed in Arkhangelsk, Leningrad, Moscow, Tula, Kursk, Nizhny Novgorod, Voronezh regions, the republics of Bashkortostan, Tatarstan, Mari-El, Mordovia, ...

Sandstones with thin layers of gypsum), it can be assumed that favorable conditions for the formation of karst landforms have formed in the area we are studying. 1.3 Features of the tectonic structure Nyuksensky district The territory of the Nyuksensky region is located in the north-west of the Russian plate, which is characterized by a block structure of the crystalline foundation. Lies within...

Thick-layered marbled limestones), and with the fact that a significant part of the sediments is confined to the most elevated part of the peninsula. In the foothill and steppe parts of Crimea, karst phenomena are also common, yet it is the leveled summit surface Crimean mountains(yaily) is considered a classic area of ​​karst distribution. Karst within the Crimean Mountains...

Underground watercourses; 6) colmatation exc. - fine-earth material brought by temporary surface and groundwater and filling underground cavities; c) obstructions, which occur when cave vaults collapse; d) sinter formations (stalactites, stalagmites, etc.); e) organogenic formations (accumulation of animal bones, etc.). O. p. have insignificant thickness, irregular intermittent lens-shaped shape, non-layered or coarsely layered structure. Several deposits of Fe and Mn ores, bauxites, and others are associated with O. caves. In caves, bone remains of Stone Age humans and objects of his material culture are often found, the study of which provides significant assistance for the stratigraphic division of Quaternary exc.

Geological Dictionary: in 2 volumes. - M.: Nedra. Edited by K. N. Paffengoltz et al.. 1978 .

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