Volcanic processes within the Petavius crater, nearside of the Moon

This study presents a detailed investigation of compositional data (e.g., Moon Mineralogy Mapper (M³), Kaguya mineral abundance map) and gravity data (Regional, residual, and crustal thickness) to understand the volcanic history of Petavius crater (~ 180 km diameter crater centered at 25.3° S, 60.4° E). Spectral analysis of M³ data reveals the presence of feldspar mineral-plagioclase and olivine at the central peak and other mafic minerals like high and low pyroxene in distinct mare units. The composition of volcanic units are mafic with dominant phases of olivine, pyroxene and plagioclase mineral. Primary melt compositions simulated using the COMAGMAT model suggest that the magmas are Mg-rich (MgO = 10.3-24.5 wt%), and the thermal regime of the Petavius mantle was not anomalously hot (i.e., > 1500 °C). Bouguer gravity anomalies show an irregular high (~ 20 mGal) over the central peak towards the southwest of the crater and a minor poorly spread associated negative annulus. The fractures on the floor are probably linked with an underlying magmatic sill of high density, which may be affecting the observed positive Bouguer Gravity Anomaly patterns. The crustal thickness varies from 27 to 29 km at the center, 30-32 km at the floor, and 33-39 km at the rim of the crater. Considering all these points, we conclude that mare material that erupted through floor fractures of the crater floor was likely the result of magmatic intrusion within the fractured crust underneath the crater floor.