Which rock type is specifically susceptible to carbonation due to its composition?

Limestone is specifically susceptible to carbonation due to its geological composition, primarily being made up of calcium carbonate (CaCO3). When carbon dioxide in the atmosphere combines with water, it forms carbonic acid, which can dissolve calcium carbonate. This process of carbonation alters the rock structure and can lead to significant geological features such as sinkholes and caves. The solubility of limestone in weakly acidic conditions makes it highly vulnerable to weathering, especially in environments where carbonic acid is formed through the natural process of soil respiration.

In contrast, granite, basalt, and sandstone have different mineral compositions that make them less susceptible to carbonation. Granite is primarily composed of quartz and feldspar, which are much more resistant to chemical weathering compared to limestone. Basalt is an igneous rock made largely of pyroxene and olivine, which also do not readily react with carbonic acid. Sandstone, primarily made of quartz grains, is generally more resistant than limestone when it comes to carbonation, although it can undergo physical weathering and other forms of chemical weathering. Thus, limestone's specific chemical makeup is what predominantly subjects it to carbonation processes.