Extended Data Fig. 4: Predicted distribution of late-stage magma ocean for a simple pre-SPA basin crustal thickness model.
From: Southward impact excavated magma ocean at the lunar South Pole–Aitken basin
The model shown is as in Fig. 3 but using only spherical harmonic degrees 1 and 2 in the pre-SPA basin crustal thickness model. a, Model of the pre-SPA basin degrees 1 and 2 crustal thickness distribution (global map, centred on the far side). b, Model of the thickness of the residual magma ocean at 99.88 PCS matching the final distribution of KREEP-rich material. c, Remnant magma ocean thickness at the SPA basin at the proposed time of impact at 98.3 PCS for this crustal thickness model, in which residual magma ocean is present only beneath the southwestern half of the basin, consistent with the distribution of Th-rich material in the ejecta blanket (d). In c, the outer outlined zone represents the ejecta, and the inner ellipse is based on the rim fitting (projection as in Fig. 1a).
