Master of Science
Dr. Gordon Osinski
Dr. Livio Tornabene
Impact cratering is a ubiquitous geological process that has shaped planetary bodies of the Solar System and beyond. While the impact cratering record on Earth has been poorly preserved, the Martian surface is characterized by a very old and cratered terrain. Central uplifts within complex impact craters are of particular interest as they expose deep-seated material, some of which may correspond to samples of the early Martian crust. Central uplift formation is, however, still a poorly understood geological process. This research investigated the origin of the exposed bedrock in the central uplifts of two Martian complex craters as well as the emplacement, distribution, and extent of allochthonous crater-fill deposits. This research entailed detailed decametre- to metre-scale mapping of morphological and structural observations with compositional analysis. Two complex craters located within Noachian-aged terrains, Alga (333.3 °E, 24.3 °S; ~19 km in diameter) and Verlaine (64.1 °E, -9.2 °S; ~39 km in diameter) were selected for this study. The exposed massive and fractured bedrock (MFB) in Alga is enriched in olivine and low-calcium pyroxene. Verlaine is characterized by MFB enriched in olivine, some of which is altered to Fe/Mg-rich clays, as well as megabrecciated bedrock. Both central uplifts are characterized by a diversity of potential impact melt-bearing lithologies that cover a major proportion of the uplifts. Structural mapping revealed that lineaments are oriented radially and concentrically, which corroborate structural assessments of terrestrial impact structures.
D'Aoust, Bianca, "Morphological, Structural and Spectral Mapping of the Central Uplifts of the Alga and Verlaine Craters, Mars" (2015). Electronic Thesis and Dissertation Repository. 3441.