Mohoroviidiszkontinuitásnál

The Mohorovičić discontinuity, often shortened to the Moho, is the geological boundary between the Earth's crust and the mantle. It is defined by a sudden increase in the velocity of seismic waves as they pass through this boundary. This change in velocity is attributed to a significant difference in the rock composition and density between the crust and the mantle. The crust is generally less dense and composed of lighter silicate rocks, while the mantle consists of denser, ultramafic rocks.

The existence of the Moho was first inferred by the Croatian seismologist Andrija Mohorovičić in 1909 based on his analysis of earthquake seismograms. He observed that seismic waves from an earthquake traveling through the Earth's interior arrived at seismograph stations at different times depending on their path. By studying these travel times, he deduced the presence of a distinct boundary where wave velocities changed, indicating a difference in the material properties.

The depth of the Mohorovičić discontinuity varies significantly across the Earth's surface. It is typically shallower beneath continents, averaging around 30-35 kilometers, and can extend to 70 kilometers or more under major mountain ranges. Beneath oceanic crust, the Moho is much shallower, usually found at depths of 7-10 kilometers below the seafloor. The understanding of the Moho is fundamental to seismology and plate tectonics, providing crucial information about the structure and composition of the Earth's lithosphere.