the MgSiO3–Al2O3 system, has an increase of Al2O3 with an increasing
pressure (Irifune et al., 1996; Wood, 2000). If so, the Al2O3 content in
MgSi-perovskite may prove to be a barometer for lower-mantle mineral
associations; and, in this case, the São Luiz association is the deepest
among those observed to date.