Ground water I think you meant! It is slightly acidic, primarily from dissolved atmospheric CO2, so can dissolve limestone given enough time.
The acid in the water forms it
Other way round! Water and/or air are in caves.:-) Most of the world's caves have formed / are forming in limestone.
caves
Almost all caves were formed by the actions of water. It dissolves the rock and and forms the caverns and spectacular views.
When limestone dissolves, the dissolved material forms ions, primarily calcium and bicarbonate ions, in the water. These ions can then be carried away by the water through rivers or groundwater. Over time, this process can lead to the formation of caves and sinkholes.
because they were to HEAVY
Erosional caves are formed when water dissolves and carves through soluble rock formations like limestone, creating passageways and chambers underground. Over time, the continuous flow of water erodes the rock and forms distinctive cave structures. As the water table changes and the rock continues to weather, erosional caves can further evolve and change shape.
Caves are mainly formed through the process of chemical weathering, particularly the dissolution of limestone by acidic water. This process is known as karst erosion. Additionally, caves can also be formed through mechanical erosion, such as the action of flowing water wearing away softer rock layers.
Karst caves, and it is the majority of caves; formed by acidic ground-water dissolving the limestone.
Acidic ground water (rain-water that has absorbed atmospheric carbon dioxide to form carbonic acid) forms caves by dissolving the limestone as it flows through the joints & other discontinuities in the rock mass.
Water in caves can vary in acidity depending on factors such as the rock composition and interactions with organic matter. In some caves, groundwater can become acidic due to the presence of minerals like sulfuric acid from rock weathering processes. However, not all water in caves is necessarily acidic, and some may be neutral or even slightly alkaline.
Caves are formed by rain water peculating through sedimentary rock such as limestone, chalk or sandstone. Over millions of years the water will dissolve away the rock, forming potholes, which can enlarge into caves and caverns.