An ophiolite is a section of the Earth's crust that has been uplifted and exposed above sea level. It typically consists of a sequence of rock types, including peridotite, gabbro, diabase, and basalt. Ophiolites are important for studying the processes of oceanic crust formation and the dynamics of tectonic plates. These formations often occur at convergent plate boundaries, where an oceanic plate is subducted beneath a continental plate. Ophiolites provide valuable insights into the composition and structure of the Earth's mantle and oceanic lithosphere, making them significant for geological research and understanding plate tectonics.