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Caves and their peculiarities

A cave is a natural cavity in the upper layer of the earth’s crust, which has at least one exit to the surface. Sometimes caves are the most complicated systems of underground passages and halls, having a length of hundred or two kilometers.

Classification of caves by origin

Depending on the origin of the cave, it can be attributed to one of five groups:

“Karst caves are not only the largest group, but also the most interesting, because they have the greatest depth and length.

– Tectonic caves arise as a result of tectonic activity. They represent various faults and cracks formed in the earth’s crust.

– Ice caves represent a very beautiful spectacle, because they are formed in the glaciers. It happens either due to huge cracks in the ice, or due to underground thermal waters. The latter are capable of creating large, beautiful halls under ice.

– Volcanic caves are formed during eruptions of volcanoes. This occurs as a result of freezing of lava flows. They can create large and long aisle-pipes, on which earlier lava flowed.

– Erosion caves arise, mainly as a result of exposure to water, which, as is known, and stone sharpens. That is exactly what is happening. For thousands of years, underground waters create paths and cavities in the thick of the earth.
Classification of caves by size

Speaking of caves, first of all, usually, they are interested in its depth. And here it is necessary to understand what exactly is meant by this concept. The depth of the cave is the distance between its lowest point and the highest point (usually this point is the entrance to the cave, but not always). The deepest caves in the world have a depth of 1.5-2 km, and only one of them has crossed the two-kilometer boundary. What’s interesting is that the cave may be underground a bit deeper than you can think of, based on numbers. This happens, for example, if the entrance is 500 meters underground. Yes, plus, say, 1 kilometer deep of the cave, and it turns out that the depth of the cave is 1 km, but underground it is at a depth of 1.5 km.
The maximum depth at which caves may exist is 3 kilometers. Below, the underground passages of the caves can not be located, because they can not withstand the pressure of overlying rocks. However, this does not mean at all that there are no cavities and cracks in the earth’s crust at large depths. There are, moreover, in large quantities. Another thing is that they are not integrated into the system.

Also an important indicator for caves is their length. And here the dependence from depth is traced: the longest caves, as a rule, have a relatively small depth, from 15 meters to a kilometer. But their uniqueness is not in the depth. And the fact that they can run underground hundreds of kilometers. Interestingly, almost all of the longest caves have a length of about 200 kilometers. And only one representative strongly stands out in this list – Mammoth Cave. It surpasses all other caves in this index more than twice, and has a length of 651 km with superfluous.

Combining these two most important indicators, one can list the largest caves in the world. True, not only those caves that have the greatest length or depth are interesting. The most interesting caves can be small in size, but have a huge historical significance. Or to represent intricate labyrinths. Or just be insanely beautiful. We also included them on the list.

Reed Flute Cave
The author of the photo is SteFou !, the link to the original (photo has been changed).

In our world, more and more amuletologists are becoming more and more amateur, as many people find it pleasure to go down to the depths of the earth, again and again, into the realm of darkness. It is these people who provide a lot of interesting information, contributing to the development of speleology. But you just think yourself, the deepest caves stretch down a couple of kilometers. Deeper than a few kilometers nobody descended. And who can say what is in the bowels of our planet? As the research shows, at a depth of 10 km, for example, quite acceptable conditions for the existence of many organisms, including animals. And there there is a lot of moves and cracks, some of which flow underground rivers. And where is water, there is also life.

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