Omphacite is the dominated phase in the subducted oceanic crust in the Earth's upper mantle. The Mid-Ocean Ridge Basalt, which makes up oceanic crust, goes through ultrahigh-pressure metamorphic process and transforms to eclogite at depth ~60 km in the subduction zones.[8] The major mineral components of eclogite include omphacite, garnet and high-pressure silica phases (coesite and stishovite).[2] As depth increases, the omphacite in eclogite gradually transforms to majoritic garnet.