A study of the deepest caves in the world

• Exploring the world of the deepest caves in

People rarely explore the vast and unexplored underground worlds, but not National Geographic photographer Stephen Alvarez, who throughout his career studying and photographing the largest and deepest caves in the world.

Cave called a cavity in the ground, communicating with the surface of one or more inlets.

The largest cave represent complex system of passages and halls are often total length of up to several tens of kilometers.

according to their origins Caves can be divided into 5 groups: tectonic, erosion, ice, volcanic, and, finally, the largest group - karst. Let's talk about them in more detail.

As already mentioned, the vast majority of caves - karst. It is these caves have the greatest length and depth.

The karst caves are formed due to the dissolution of the rock with water, so they are found only where there is a soluble rocks: limestone, marble, chalk, gypsum and salt.

Tectonic caves can occur in any breed in the formation of tectonic faults. They are found in the sides are deeply embedded in the plateau of the river valleys, where massive amounts of rock break away from the sides, forming cracks.

These cracks sometimes form a fairly deep vertical cave to a depth of 100 meters.

third type of caves - erosional. They are formed by mechanical rock, i.e. "Rout" water containing a pellet of solid material. Often these caves formed by the sea under the influence of the surf, but they are small.

The spectacular glacier caves are formed in the body from meltwater from glaciers.

Meltwater forms passages, sometimes passable to humans. The length of such caverns may be several hundred meters, depth - up to 100 meters or more.

Also, the ice cave can be formed in the glacier at the exit site located under the glacier underground thermal springs. Hot water is able to do in the ice bulk picture. Thermal glacial caves are found in Iceland, Greenland and reach rather large sizes.

The latter type - a volcanic cave. They occur in volcanic eruptions. lava cools, a solid crust is covered, forming lava tube. After closure eruption lava flows from the lower end of the tube, but remains a cavity inside the tube.

The lava caves can become very large, up to 65.6 km length and 1100m depth.

In addition, there are lava tubes vertical volcanic caves - volcanoes.

The living world of caves is not very rich, however, some of the animals found here. Firstly, it's bats that use the caves as a shelter or for wintering. And bats often fly in remote and inaccessible areas of caves, well-guided in the narrow labyrinth passages.

In addition to bats in some caves inhabited by insects, spiders, shrimp, salamanders and fish. All cave species adapt to the dark, and many of them lose their organs of vision.

As we know from history, primitive people used the caves around the world as a home. More often settled in the caves of animals.

Typically, the water is found in many caves and karst caves owe their origin to it. Not uncommon and beautiful underwater cave. About them we were told in detail.

Most caves air breathable, though there are caves, where you can only be in masks.

Furthermore caverns having to determine the yield of the surface, in the Earth's crust is closed underground cavity. The deepest underground cavity length of 2950 meters of drilling has been discovered on the coast of Cuba.

In the solar system, other than Earth, caves found on the Moon and Mars.