Ancestral cavern entrance timelapse, with flowing clouds rapidly in the background.
Caves are formed by various geologic processes and can be variable sizes. These may involve a combination of chemical processes, erosion from water, tectonic forces, microorganisms, pressure, and atmospheric influences. For karst caves the maximum depth is determined on the basis of the lower limit of karst forming processes, coinciding with the base sequences limestone,which may be lower than the erosion base due to the presence of siphon channels. Most caves are formed in limestone by dissolution.