Vestiges of a lunar ilmenite layer following mantle overturn revealed by gravity data

Liang, Weigang1; Broquet, Adrien1; Andrews-Hanna, Jeffrey C.1; Zhang, Nan2; Ding, Min3; Evans, Alexander J.4

2024-04-01

10.1038/s41561-024-01408-2

NATURE GEOSCIENCE   影响因子和分区

1752-0894

1752-0908

["The lunar crust and mantle formed through the crystallization of a magma ocean, culminating in a solid cumulate mantle with a layer of dense ilmenite-bearing cumulates rich in incompatible elements forming above less dense cumulates. This gravitationally unstable configuration probably resulted in a global mantle overturn, with ilmenite-bearing cumulates sinking into the interior. However, despite abundant geochemical evidence, there has been a lack of physical evidence on the nature of the overturn. Here we combine gravity inversions together with geodynamic models to shed light on this critical stage of lunar evolution. We show that the observed polygonal pattern of linear gravity anomalies that surround the nearside mare region is consistent with the signature of the ilmenite-bearing cumulates that remained after the global mantle overturn at the locations of past sheet-like downwellings. This interpretation is supported by the compelling similarity between the observed pattern, magnitude and dimensions of the gravity anomalies and those predicted by geodynamic models of the ilmenite-bearing cumulate remnants. These features provide physical evidence for the nature of the global mantle overturn, constrain the overturn to have occurred before the Serenitatis and Humorum basin-forming impacts and support a deep Ti-rich mantle source for the high-Ti basalts.","The Moon's gravity field preserves a record of the overturn of the early lunar mantle and sinking of dense ilmenite-bearing cumulates, according to a comparison of Gravity Recovery and Interior Laboratory gravity data and geodynamic models."]

SCI

英语

其他

NASA Lunar Data Analysis Program[80NSSC22K1340]

Geology

Geosciences, Multidisciplinary

WOS:001198567300002

NATURE PORTFOLIO

Web of Science

1.Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA
2.Peking Univ, Sch Earth & Space Sci, Key Lab Orogen Belts & Crustal Evolut, Beijing, Peoples R China
3.Southern Univ Sci & Technol, Shenzhen, Peoples R China
4.Brown Univ, Dept Earth Environm & Planetary Sci, Providence, RI USA

Liang, Weigang,Broquet, Adrien,Andrews-Hanna, Jeffrey C.,et al. Vestiges of a lunar ilmenite layer following mantle overturn revealed by gravity data[J]. NATURE GEOSCIENCE,2024,17(4).

Liang, Weigang,Broquet, Adrien,Andrews-Hanna, Jeffrey C.,Zhang, Nan,Ding, Min,&Evans, Alexander J..(2024).Vestiges of a lunar ilmenite layer following mantle overturn revealed by gravity data.NATURE GEOSCIENCE,17(4).

Liang, Weigang,et al."Vestiges of a lunar ilmenite layer following mantle overturn revealed by gravity data".NATURE GEOSCIENCE 17.4(2024).