More than 300 limestone caves can be found in the
state parks of
Petar,
Intervales and
Jacupiranga which form part of the
Atlantic
Rainforest
Southeast Reserves
World Heritage Site
in the south of
São Paulo State.
The caves are part of an espactacular
karst landscape, which was formed during million of years
by the chemical dissolution of limestone.
When the resultant of this reaction, a calcium bicarbonate (Ca(HCO3)2) solution, runs along the cave ceiling, it looses its velocity,
forms drops, releases the excess carbon dioxide (CO2) and causes the much less soluble calcium carbonate (CaCo3) to be deposited.
A
stalactite is formed.