ProgressLayering of subcontinental lithospheric mantle

Recent seismic studies reveal a sharp velocity drop mostly at ∼70-100 km depth within the thick mantle keel beneath cratons, termed the mid-lithosphere discontinuity (MLD). The common presence of the MLD in cratonic regions indicates structural and property layering of the subcontinental lithospheric mantle (SCLM). The nature and origin of the MLD, and many issues associated with the layering of the SCLM are essential to understand the formation and evolution of continents, and have become frontier subjects in the Earth sciences.