A reassessment of the volcanic history of western South Pole-Aitken Basin based on
geologic mapping
R.A. Yingst, F.C. Chuang, D.C. Berman, S.C. Mest
1Geological Society of America – Denver, CO, October 2013Geologic map at 1:250,000 of Lunar Quadrangle 29-Planck
Overview
• Geologic setting of the mapping site.
• Methodology; criteria for identifying volcanics.
• Implications
– More diverse modes of emplacement
– Greater area covered by volcanics
2Geological Society of America – Denver, CO, October 2013
3
Planck Quadrangle (outlined in black), with large impact structures noted. Map was created at 1:2,500,000-scale.
Geological Society of America – Denver, CO, October 2013
LROC WAC mosaic of Planck Quadrangle
Datasets
15 kmN
Geological Society of America – Denver, CO, October 2013
LROC WAC mosaic of Jules Verne, Planck Quadrangle (~100 m/pxl)
Clementine multispectral mosaic of Jules Verne (~100-300 m/pxl)
LOLA topographic of Jules Verne (~1 m/pxl vertical)
Volcanic deposits• Volcanic deposits identified by albedo, texture,
morphology and spectral signature.
• - Mare deposits
• - Pyroclastics
• • Other volcanically derived deposits
• - Cryptomare candidates
5Geological Society of America – Denver, CO, October 2013
Geological Society of America – Denver, CO, October 2013
Mare deposits
Pauli
12 kmN
Geological Society of America – Denver, CO, October 2013
Pyroclastic deposits
N Jules Verne
20 kmN
Geological Society of America – Denver, CO, October 2013
Other volcanically-
derived deposits
N
Geological Society of America – Denver, CO, October 2013
7 km
7 km
Jules Verne P
N
Other volcanically
derived deposits
Geological Society of America – Denver, CO, October 2013
5 km
5 km
N
Jules Verne
Cryptomare material
N of Planck
15 kmN
Geological Society of America – Denver, CO, October 2013
Geological Society of America – Denver, CO, October 2013
Results
22 mare deposits, 18 other volcanic deposits (7 are newly mapped).
An additional 3,000-5,000 km2 covered by other volcanics (5% more).
Broader range of volcanic expressions than previously mapped.
Geological Society of America – Denver, CO, October 2013
Conclusions
Greater surface area covered by volcanics implies a greater volcanic flux.
More variations in eruptive style than previously suspected — We infer mode of emplacement of volcanic deposits (an indication of conditions at depth) was more diverse than previously thought.
Other volcanics associated with fractures — tectonic trigger?
No estimate yet on the stratigraphy of these deposits and how morphology varies as a function of time.
Geological Society of America – Denver, CO, October 2013