Thermodynamic constraints on the petrogenesis of massif-type anorthosites and their parental magmas

Development of computational modeling tools has revolutionized studies magmatic processes over the last four decades. Their refinement from binary mixing equations to thermodynamically controlled geochemical assimilation models provided more comprehensive and detailed constraints an array systems. One questions that not yet been vigorously studied using thermodynamic is origin massif-type anorthosites. The parental melts these intrusions are hypothesized be either mantle-derived high-Al basaltic undergo crustal contamination or monzodioritic derived directly lower crust. On other hand, many suggest rocks do represent but instead crystal remnants residual liquids left after fractionation melts. Regardless source composition, magmas produce anorthosites have suggested undergone polybaric (~1000–100 MPa) fractional crystallization while ascending through lithosphere. We conducted melting, assimilation-fractional crystallization, isobaric major element two constrained tools, Magma Chamber Simulator (MCS) rhyolite-MELTS, test suitability study petrogenesis Comparison our with a large suite whole-rock data suggests anorthosite were basalts produced when hot partial assimilated material at Moho levels. These contaminated then experienced different levels (~40 5 km) producing crystallized as rocks. Model outcomes also support suggestion cumulates during likely underwent density separation, thus plagioclase-rich anorthositic modeled linked four-stage model describes key petrogenetic generate presented framework enables further individual MCS involving trace isotope constrains.