MohoroviČiĆ discontinuity (moho)

Joint Geophysical‐Petrological Modeling on the Ivrea Geophysical Body Beneath Valsesia, Italy: Constraints on the Continental Lower Crust

“…While the “geophysical Moho” defines the sudden change in compressional wave velocities from typically <7 km/s to >8 km/s, the “petrological Moho” transition zone corresponds to the level where plagioclase disappears from the crystallizing assemblage within the cumulates of underplated mafic magma (Müntener & Ulmer, 2006). The “petrological Moho” then corresponds to the disappearance of feldspar in the downward gradation of gabbroic cumulates to ultramafic cumulates as observed in ophiolite and arc sections (Bowes, 1989; Burg et al., 1998). In the exposed crust‐mantle sections, it is possible to apply a thorough investigation of spatial and temporal relationships between lower crustal rock units and even with the upper crust, which cannot be obtained by xenolith investigations alone.…”

“…Moho" then corresponds to the disappearance of feldspar in the downward gradation of gabbroic cumulates to ultramafic cumulates as observed in ophiolite and arc sections (Bowes, 1989;Burg et al, 1998). In the exposed crust-mantle sections, it is possible to apply a thorough investigation of spatial and temporal relationships between lower crustal rock units and even with the upper crust, which cannot be obtained by xenolith investigations alone.…”