Lunar Procellarum KREEP Terrane (PKT) Stratigraphy and Structure with Depth: Evidence for Significantly Decreased Th Concentrations and Thermal Evolution Consequences

Dating from the lunar magma ocean solidification period, Procellarum KREEP Terrane (PKT) occupies 16% of surface but has a much higher thorium abundance compared to rest Moon and is thus interpreted carry 40% radioactive elements by volume in form an anomalously thick KREEP-rich layer. Subsequent research focused on processes responsible for PKT concentration localization (e.g., degree-1 convection, farside impact basin effects, etc.), effect high-radioactivity thermal evolution topography relaxation, mantle heating, late-stage mare basalt generation, etc.). Here we use stratigraphic approach new crustal thickness data probe nature with depth. We find that most characteristics can be explained sequential cratering events excavated redistributed surface/near-surface thinner Th-rich layer at depth, implying no anomalous conditions thickness, abundances, geodynamics, effects or generation are likely required as previous studies.