Caves do not really start out as caves. That is a strange thought! They form in rocks many thousands of years. Many caves are formed with limestone, marble, gypsum, and dolomite. These are rocks which can dissolve quickly over time.
The cave is defined as a naturally occurring hollow region inside the earth. Some erosional process forms many caves. The most prominent exception is the hollow lava tubes like those found in the Hawaiian Islands. The caves’ formation depends on upon topographic, geologic, and the hydrologic factors. These key factors determine how and where caves develop, as well as their shape and structure. The study of caves is referred to as speleology. Some caves may be tiny hillside openings whereas others comprise of huge chambers and the interconnecting mazes and tunnels. Openings to the surface may be big gaping holes or small crevices.
Caves hosted in the rocks other than limestone are often formed by various water erosional processes. For instance, rivers running through the canyons with steep walls wear down the rock at parts where the current is very powerful. Such caves often have huge openings and aren’t very deep. Caves of this kind can exist in the southwestern US and were at once inhabited by ancient American Indians called Cliff Dwellers. Sea caves are developed by waves frequently crashing against steep walls or cliffs. Usually, these caves can only be entered during low tide. The ice caves are also formed in icebergs and glaciers by meltwater which drains down crevices in the ice.
The development and formation of caves are called speleogenesis. Caves are formed by different geologic processes and can be of distinct sizes. These may also involve a combination of erosion from water, chemical processes, microorganisms, tectonic forces, pressure, and the atmospheric influences.
It’s approximated that the maximum depth of a cave can’t be more than 9,800 ft. (3,000 meters) because of the pressure of the overlying rocks. For karst caves, the optimum depth is determined based on lower limit of karst forming processes that coincide with the base of any soluble carbonate rocks. Many caves are developed in limestone by dissolution.
Caves exist all over the world, but only a minor portion of them have been explored and even documented by cavers. The distribution of the documented cave systems is broadly skewed toward nations where caving has been prominent for several years (like Italy, France, Australia, the United Kingdom, the United States, etc.). As a result, all explored caves are found mostly in Asia, Europe, Oceania and North America, but are sparse in Africa, South America, and Antarctica.
This is a general generalization, as huge expanses of Asia and North America lack documented caves while areas like parts of Brazil and the Madagascar dry deciduous forests contain several documented caves. As various research the world’s expanses of the soluble bedrock, the distribution of all documented caves is likely to shift. For Instance, China, regardless of containing around half the exposed limestone of the world – over 1,000,000 square kilometers (390,000 sq. mi)—has relatively less documented caves.
Here are 5 interesting facts about caves:
1. The deepest documented cave is Voronya Cave in Georgia, at 7,208 ft. (2,197 m).
2. The world’s 3 longest documented cave systems are Jewel Cave, South Dakota, USA, 267.6 kilometers (166.3 miles), Sistema Sac Actun/Sistema Dos Ojos, Mexico, 319 kilometers (198.2 miles), and Mammoth Cave, Kentucky, USA, 651.8 kilometers (405 miles).
3. Sea caves (or littoral caves) are situated on the coast, formed by the tidal action and continual wave that weakens or erodes sea cliffs.
4. Scientific or recreational exploration of a cave system is known as spelunking, potholing or caving.
5. The most popular types of cave formation are the solutional caves. They’re developed by natural acids in the groundwater dissolving soluble rock like limestone (or sometimes dolomite, chalk, gypsum or marble).