Paper No. 1
Presentation Time: 8:00 AM
EXPLORING THE MOON WITH LRO: CHARACTERIZING VOLCANISM ON THE LUNAR SURFACE (Invited Presentation)
The first three years of Lunar Reconnaissance Orbiter (LRO) operations have led to advances in our understanding of lunar volcanism. LRO Diviner observations provided the first direct evidence of silicic exposures on the lunar surface, including Gruithuisen, Mairan T, and Hansteen Alpha [1–3], and the newly-discovered farside silicic volcanic complex at Compton-Belkovich [4]. LROC topographic data derived from geometric stereo observations permit the analysis of key volcanic feature characteristics, including slope and volume estimates, definition of flow features, depression morphologies, and boulder populations. The LRO Science Team characterized the morphometric properties and roughness of more than 150 domes and ~90 cones in the Marius Hills region showing that the Marius Hills volcanic constructs are not silicic [5-7]. The flow lengths and slopes indicate that the unique morphology of the Marius domes are instead primarily controlled by effusion dynamics. Oblique views of the mare pit craters in the Marius Hills, Mare Tranquillitatis, and Mare Ingenii show multiple coherent layers, each 3-14 m thick, indicating that eruptions produced a series of ˜10 m thick flows or flow lobes [10]. A survey revealed localized pyroclastic deposits within floor-fractured craters Anderson E and F on the lunar farside, isolated from other known pyroclastic deposits [11]. LRO observations suggest that the unique morphology of the Ina-D caldera is due to inflated effusive flows, and other Ina-type features have been observed [12,13]. LRO science results are adding to our understanding of lunar volcanic processes while defining key targets for future robotic and human exploration.
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