Reference

Serpentine is formed from olivine through a process known as serpentinization, which involves a series of chemical reactions when olivine-rich rocks interact with water and carbonic acid. This process can be summarized by the following reaction:

[ \text{Olivine} + \text{water} + \text{carbonic acid} \rightarrow \text{serpentine} + \text{magnetite} + \text{magnesite} + \text{silica} ]

Serpentinization occurs when water-rich fluids, which may contain dissolved carbon dioxide forming carbonic acid, circulate through ultramafic rocks rich in olivine and pyroxene. The carbonic acid lowers the pH, enhancing the dissolution of minerals and promoting the formation of serpentine, a group of hydrous magnesium iron phyllosilicates.

This transformation is significant as it can lead to the production of hydrogen gas, which has implications for both geological processes and potential industrial applications such as hydrogen production. Serpentine formation also plays a role in the deep carbon cycle and can influence the physical properties of rocks, such as reducing their permeability.

The process is complex and can involve multiple steps and intermediate products. Experimental studies have been conducted to understand the extent and nature of mineral transformations during serpentinization, including the role of magnesium isotope fractionation. Serpentine rocks are of interest in the study of hydrothermal systems and have been linked to the existence of certain types of life in extreme environments.