Chemical weathering.
Rain-water is slightly acidified by absorbing atmospheric CO2. On leaching through the joints, bedding-planes and faults with the mass of limestone, this "carbonic acid" slowly dissolves the calcium carbonate that is limestone's primary constituent.
NB: This is a very basic introduction to a very much more complex and subtleinteraction of geology, hydrology and long-term climate specific to each cave's location.
caverns
Erosion is displacement of solids (sediment, soil, rock and other particles) usually by the agents of currents such as, wind, water, or ice by downward or down-slope movement in response to gravity or by living organisms (in the case of bioerosion).
Sinkholes and caverns are formed from carbolic acid. This carbolic acid dissolves rock which creates the spaces that form the sinkholes and caverns. The carbolic acid is created when carbon dioxide dissolves in water.
As it starts to break down all of the rock it starts to create space therefor a cave or cavern can be made.
The potholes and caverns formed in limestone by water seeping through limestone bedrock is an example of such weathering.
tunnels, caverns, caves, ravines
Caverns can be under water and underground.
water
caverns
No, most caverns form below the water table. Caverns are typically formed by the dissolution of underground limestone or other soluble rocks by water, and this process usually occurs below the water table where the rocks are saturated with water.
Caverns are typically formed through a process known as karstification, where groundwater dissolves soluble rocks like limestone and carbonate rocks over time. This dissolution, along with other factors such as erosion and tectonic forces, can create underground cavities and passageways that eventually turn into caverns.
Limestone and water are usually involved.
caverns
groundwater
No caverns are not all the same size. Cave size depends on the rock and the amount of water passing through.
Caves, caverns, and sinkholes are typically formed by the dissolution of soluble rocks such as limestone, dolomite, or gypsum by water. Over time, water erodes and dissolves the rock, creating underground cavities and passages. Eventually, these cavities can collapse or become exposed at the surface, forming caves, caverns, and sinkholes.
The animals that live in Linville Caverns are the animals that can withstand a lot of cold. They are the types of animals that need a lot of water as well.