Geophysics S-waves in the outer core. This indicates that the outer core is liquid, because liquids cannot support shear. The outer core is liquid, and the motion of this highly conductive fluid generates the Earth's field. The inner core, however, is solid because of the enormous pressure. Reconstruction of seismic reflections in the deep interior indicate some major discontinuities in seismic velocities that demarcate the major zones of the Earth: inner core, outer core, mantle, lithosphere and crust. The mantle itself is divided into the upper mantle, transition zone, lower mantle and "D′′" layer. Between the crust and the mantle is
The Layer Monument Layer Quaternity correspond to the alchemical "deities" of Apollo, Luna, Mercurius and Vulcan as named in "Atalanta Fugiens" (1617) by the German alchemist-physician Michael Maier (Emblem XVII). Collectively the Layer Quaternity are a unique alchemical mandala. Through polarized symbolism they delineate essential coordinates associated with Mandala art, namely Space (Heaven and Earth) and Time (Young and Old). Utilizing variety and multiplicity, key attributes of Northern Mannerist art, they also represent fundamental aspects of the human condition, namely, gender, youth and age, pleasure and suffering. A fifth, uniting symbol, a skull, is located at the very centre of the monument. The