Topography Based Surface Analysis and Morphological Correlation at the Northern Plains of Mars

Topography based surface analysis and morphology correlation for the northern hemisphere of Mars – The topographic analysis of the Martian surface might help to understand basic geomorphological connections and improve our understanding in the surface features of the Earth too. In this work we correlated the statistical topographic parameters and the remote sensed image based appearance of various locations along a meridional stripe at the northern hemisphere of Mars. The topographic location of nearly horizontal plains suggests that the erosion and re-deposition was not effective enough to transport the sediments at the topographic lowerst point at 50 km distance scale. Great difference could be identified between the topographic height distribution pattern of different analyzed terrains, suggesting different variability and complexity in the range in surface feature types there. Terrains resembling the pediment-like structures also could be at the analyzed terrains on Mars, but their firm identification requires more detailed analysis. The statistical based topography analysis could give useful input for detailed surface research in geomorphology

Shock and thermal annealing history of the ALH 77005 Martian meteorite: a micro-Raman spectroscopical investigation

Abstract We studied optical microscopic and micro-Raman spectroscopic signatures of shocked olivine from the ALH 77005 Martian meteorite sample. The purpose of this study is to document pressure and temperature-related effects in olivine over the entire sample, which can aid in understanding structural changes due to shock metamorphism and the post-shock thermal annealing processes of lherzolitic Martian meteorites. According to the optical microscope observations, three areas may be discernible in olivine of the ALH 77005 in the vicinity of the melt pocket. The first area is the thermally undisturbed part of a grain, which contains a high density of shock-induced planar microdeformations such as Planar Deformation Features (PDFs) and Planar Fractures (PFs). Compared to the first area, the second area shows less shock-induced microstructures, while the third area is a strongly recrystallized region, but not formed from a melt. A common Raman spectral feature of these olivines is a regular doublet peak centered at 823 and 852 cm−1; additionally, two new peaks at 535 and 755 cm−1 appear in the weakly annealed transition zones