Stability of rock slopes in Valles Marineris, Mars
نویسنده
چکیده
[1] New slope measurements from the Mars Orbiter Laser Altimeter (MOLA), in conjunction with the Rock Mass Rating system (RMR), permit inversions of slope height and angle from wallrock and interior deposits within Valles Marineris troughs for strength and lithology. Wallrock (50 < RMR < 65) is stronger than interior deposits (30 < RMR < 55). These values are consistent with layered igneous rock beneath wallrock slopes, with interior deposits consistent with partially indurated sedimentary or volcaniclastic rocks. Larger volumes of landslide debris relative to terrestrial slides are related to the reduced Martian gravity. Seismicity along trough-bounding normal faults likely triggered the landslides in the adjacent wallrock. The weaker interior deposits are located sufficiently far from a border fault (and on its hangingwall) to have remained stable during the seismogenic faulting in Valles Marineris.
منابع مشابه
A Likely Formation Mechanism for the Hematite-rich Spherules in the Equatorial Region of Western Mars
Introduction: The gray crystalline hematite on Mars was detected in three regions, Sinus Meridiani, Aram Chaos and Valles Marineris by the thermal emission spectrometer (TES) onboard the Mars Global Surveyor (MGS) orbiter [e.g.1, 2]. The Mars Exploration Rover (MER) Opportunity confirmed that hematite-rich spherules (~ 4.2 mm) are embedded in sulfur-rich layered outcrops and accumulated on the ...
متن کاملNew insights on the runout of large landslides in the Valles-Marineris canyons, Mars
[i] Analogy with lab-scale dry granular flow experiments demonstrates that runouts and deposits heights of VallesMarineris (VM) landslides can be scaled on a curve varying primarily with the initial aspect ratio of the mobilized rock mass (before slope failure). This results suggests both that any interstitial fluid played a negligible part in the VM landslides dynamics and that mobility is not...
متن کاملPristine Noachian crust and key geologic transitions in the lower walls of Valles Marineris: Insights into early igneous processes on Mars
Valles Marineris is a unique vertical section through the uppermost kilometers of the martian crust. Its location, east of the Tharsis bulge, and its water-related history, fuel a great diversity of rock types in this area (Carr, M.H., Head, J.W. [2010]. Earth Planet. Sci. Lett. 294, 185–203). HiRISE and CRISM data available over the walls of the canyon were analyzed to infer the importance of ...
متن کاملFluvial and lacustrine activity on layered deposits in Melas Chasma, Valles Marineris, Mars
[i] Valley networks on Mars are the most obvious features attesting that different geologic processes and possibly climatic conditions existed in the past. THEMIS images reveal valley networks within Melas Chasma, in Valles Marineris, a Hesperian-age canyon system. The valley networks in Melas Chasma are dense and highly organized, and the heads of the valleys are scattered at different elevati...
متن کاملLandslides in Valles Marineris (Mars) A possible role of basal lubrication by sub-surface ice
There is much interest on the occurrence of water and ice in the past history of Mars. Because landslides on Mars are much better conserved than their terrestrial counterparts, a physical examination and morphological analysis can reveal significant details on the depositional environment at the instant of failure. A study of the landslides in Valles Marineris based on their physical aspect is ...
متن کامل