Serpentiniitit

Serpentiniitit are a group of minerals that form when peridotite, an ultramafic igneous rock, is hydrated and altered by water circulating through the Earth's crust. This process, known as serpentinization, typically occurs at low temperatures and pressures, often associated with tectonic plate boundaries. The primary minerals found in serpentinite are serpentine group minerals, which are hydrous magnesium iron silicates. These include antigorite, chrysotile, and lizardite.

The appearance of serpentinite can vary widely, ranging from dull green to almost black, and it can be massive, fibrous, or platy in texture. Chrysotile, a fibrous form of serpentine, is also known as asbestos and has been used industrially for its heat-resistant properties, though its use is now heavily restricted due to health concerns. Serpentinite rocks are relatively soft and easily weathered.

Serpentinite formations are often found in ophiolites, which are fragments of oceanic crust and upper mantle that have been thrust onto continental crust during tectonic collisions. These formations are significant in geology as they provide insights into the composition and processes of the Earth's mantle and the history of plate tectonics. Serpentinite can also play a role in geological hazards, as its lubrication properties can influence fault movement and seismic activity. In some regions, serpentinite has been explored as a material for carbon sequestration, where its minerals can react with atmospheric carbon dioxide to form stable carbonates.