Individual lava flow thicknesses in oceanus procellarum and mare serenitatis determined from clementine multispectral data

Shoshana Z. Weider (1, 2, 3) , Ian A. Crawford (1, 2) , Katherine H. Joy (1, 2, 4, 5)

1 Department of Earth and Planetary Sciences [UCL/Birkbeck]
2 CPS - Centre for Planetary Sciences [UCL/Birkbeck]
3 RAL Space - Space Science and Technology Department [Didcot]
4 LPI - Lunar and Planetary Institute [Houston]
5 The NASA Lunar Science Institute

We use multispectral reflectance data from the lunar Clementine mission to investigate the impact ejecta deposits of simple craters in two separate lunar mare basalt regions, one in Oceanus Procellarum and one in Mare Serenitatis. Over one hundred impact craters are studied, and for a number of these we observe differences between the TiO (and FeO) contents of their ejecta deposits and the lava flow units in which they are located. We demonstrate that, in the majority of cases, these differences cannot plausibly be attributed to uncorrected maturity effects. These observations, coupled with morphometric crater relationships that provide maximum crater excavation depths, allow the investigation of sub-surface lava flow stratigraphy. We provide estimated average thicknesses for a number of lava flow units in the two study regions, ranging from ∼80m to ∼600m. In the case of the Serenitatis study area, our results are consistent with the presence of sub-surface horizons inferred from recent radar sounding measurements from the JAXA spacecraft. The average lava flow thicknesses we obtain are used to make estimates of the average flux of volcanic material in these regions. These are in broad agreement with previous studies, suggesting that the variation in mare basalt types we observe with depth is similar to the lateral variations identified at the surface.

Mots clés: Cratering; Moon; spectroscopy; volcanism

Domaines: Planète et Univers [physics]

Shoshana Z. Weider, Ian A. Crawford, Katherine H. Joy. Individual lava flow thicknesses in oceanus procellarum and mare serenitatis determined from clementine multispectral data. Icarus, 2010, 209 (2), pp.323. ⟨10.1016/j.icarus.2010.05.010⟩. ⟨hal-00676221⟩