Investigating the Influences of Crustal Thickness and Temperature on the
Uplift of Mantle Material Beneath Large Impact Craters on the Moon
Abstract
In this work we examine variations in mantle uplift associated with
large lunar impact craters and basins between major terranes. We analyze
the Bouguer gravity anomalies of 100–650-km diameter lunar impact
craters using Gravity Recovery and Interior Laboratory (GRAIL)
observations and the Lunar Orbiter Laser Altimeter (LOLA) crater
database. The Bouguer gravity anomalies of 324 large impact craters
analyzed herein are primarily controlled by the uplifted crust-mantle
(Moho) interface in the central region of these impact craters, although
post-impact mare deposits contribute to the gravity anomalies of some
individual craters. The central uplift of the Moho interface is
primarily controlled by impact energy and increases to ~
30 km for a 650-km crater. Further analyses of craters in the
Feldspathic Highlands Terrane (FHT) with varied crustal thickness ()
reveal that the onset crater diameter () with an uplifted Moho interface
is dependent on the local : ~ 146+1.1(in a unit of km).
This equation also provides a quantification of the depth-dependent
attenuation of impact-induced structural uplift, using the Moho uplift
as a proxy for structural uplift. Moho uplift of large craters in the
hotter South Pole-Aitken Terrane (SPA) is not statistically different
from FHT craters, consistent with the expected thermal difference
between these terrains during the pre-Nectarian period.