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The various origins proposed for intercrater plains on Mercury and the Moon lead to divergent thermal, tectonic, and bombardment histories. Relative ages of geologic units and structures place tight constraints on their origin and on the planet's geologic history. Crater statistics, lunar geologic map analysis, and geologic mapping of a quarter of Mercury's surface based on plains units dated relative to crater degradation classes were used to determine relative ages. Such studies provided the basis for deducing the origin of intercrater plains and their role in terrestrial planet evolution. Mercury's extensive intercrater plains span a range of ages contemporaneous with the period of heavy bombardment. Most intercrater plains predate scarp formation and the formation of the hilly and lineated terrain. The age of the latter is identical to that of its probable progenitor, the Caloris basin impact. Post-Caloris plains--smoother in texture, less extensive, and confined to crater depressions--formed as cratering waned and scarp formation progressed. This research indicates that mercurian intercrater plains are volcanic deposits interbedded with ballistically emplaced ejecta and reworked by basin secondaries and smaller impacts. A greater proportion of ejecta may comprise lunar intercrater plains. Neither the lunar nor mercurian intercrater surface is primordial because each preserves pre-plains crateriforms. Ancient volcanism on Mercury is evidenced by widespread plains distribution, structurally controlled deposition, embayment of craters and basins, associated (but tentative) volcanic landforms, losses of small craters, and uncorrelated plains and crater coverage. The limited range of mercurian ejecta reduces the resurfacing potential relative to that of lunar craters. Crater densities are affected by intercrater plains emplacement, additions of secondaries, ancient basin impacts, and target physical properties. "One-plate" thermo-tectonic models best explain the geologic characteristics recognized in this study. Thermal expansion during core formation causes global extension and widespread volcanic extrusions; subsequent cooling and radial contraction form compressional scarps. Younger plains-forming materials issue from magma reservoirs in subsurface tensional zones tapped by impact fractures. The age and stress environment of these volcanic plains suggest a source greater than 40 km depth and a composition different from that of the intercrater plains.

Les travaux menés dans cette thèse se partagent entre la Lune et Mars, cibles privilégiées pour les missions d'exploration spatiales. La première partie porte sur l'instrument Interference Imaging Spectrometer (IIM) qui était à bord du satellite lunaire chinois Chang’e-1. Une méthode inédite utilisant l'angle spectrale et le concept de distance Euclidienne, et visant à supprimer les mauvais pixels de IIM, est proposée. Une nouvelle procédure de calibration est utilisée, et l'inter-étalonnage des données IIM avec des données télescopiques est amélioré. Ce nouveau jeu de données permet, après inversion, d'estimer l'abondance de FeO dans le sol lunaire. Les valeurs trouvées sont comparables aux observations du satellite américain Clementine et fournissent une nouvelle référence pour les études lunaires à venir. La seconde partie est consacrée à la modélisation du phénomène de tempêtes de poussière-fusée ("rocket dust storms") générées par des mouvements convectifs meso-echelle liés au chauffage solaire des poussières. L'objectif est de reproduire numériquement les couches de poussières détachées découvertes par l'instrument Mars Climate Sounder (NASA) dans le Modèle de Climat Global (GCM) du LMD. Les simulations montrent que, durant la saison des tempêtes de poussières (printemps et été austral), ce phénomène permet d'expliquer les couches détachées, et de reproduire les observations. Cependant, durant l'autre partie de l'année où il y a très peu de tempêtes de poussières, il semble nécessaire d'inclure dans le GCM un autre processus impliquant les vents de pente, capable de réinjecter les poussières en altitude pour maintenir les couches détachées. / Moon and Mars have been the important targets for deep space missions. The studies in this thesis include two parts. The first part is concerning Chang’e-1 Interference Imaging Spectrometer (IIM) data preprocessing and global lunar FeO inversion. In order to better preprocess the IIM data, a new method using spectral angle and Euclidean distance for removing bad pixels has been proposed. A new in-flight calibration has been conducted. And cross calibration of IIM data by using the telescopic data is improved. The processed IIM data have also been used to inverse lunar FeO abundance. The IIM-derived FeO is comparable to Clementine FeO results, and can be an alternative dataset for Moon studies. The second part is concerning parameterizing rocket dust storms and daytime slope winds in LMD (Laboratoire de Météorologie Dynamique) Mars GCM (Global Climate Model) to reproduce the detached dust layers (DDLs) observed by Mars Climate Sounder (MCS) on Mars. The simulations by the GCM including rocket dust storm parameterization show that, during the Martian dusty seasons, the rocket dust storms are the key factors to explain the observed DDLs. The formation and evolution of GCM simulated DDLs are in agreement with those of MCS observation. Meanwhile, the simulation also suggests that the large variation of the DDLs’ altitudes in dusty season are contributed by the deep convection induced by rocket dust storms. The simulations by the GCM including daytime slope winds parameterization show that with the help of daytime slope winds, the GCM can reproduce the detached dust layers in Martian clear seasons, which cannot be simulated by the rocket dust storm process.