The Mohorovičić Discontinuity, often referred to as the "Moho," is a significant geological boundary that separates the Earth's crust from the underlying mantle. It is named after the Croatian seismologist Andrija Mohorovičić, who first identified it in 1909.
The Moho is characterized by a marked change in the composition and properties of the Earth's materials. Below the Moho, the rocks are primarily denser and have a higher metallic content, while the crust, which is above the Moho, is primarily composed of lighter silicate minerals. This discontinuity is important in the study of geology and seismology as it reflects varying seismic wave velocities; seismic waves travel faster in the mantle than in the crust. The Moho's depth varies, being approximately 5 to 10 kilometers below the oceanic crust and around 30 to 50 kilometers beneath continental crust.
Understanding the Mohorovičić Discontinuity is crucial for studying Earth's internal structure, tectonic activity, and the processes that drive plate tectonics.