A downscaling approach for geological characterization of the Raditladi basin of Mercury

In this work, we combined multi-scale geological maps of Mercury to produce a new
global map where geological units are classified based on albedo, crater density and morphological
relationships with other units. To create this map, we used the 250 m/pixel mosaic of images
acquired by the narrow- and wide-angle cameras onboard the MErcury Surface, Space ENviron-
ment, GEochemistry, and Ranging (MESSENGER) spacecraft during its orbital phase. The geo-
logical mapping is supported by digital terrain model data and surface mineralogical variation
from the global mosaic of MESSENGER Mercury Atmospheric and Surface Composition Spec-
trometer observations. This map comprises the global-scale intercrater plains, smooth plains and
Odin-type units as reported in previous studies, as well as units we term bright intercrater plains,
Caloris rough ejecta and dark material deposits. We mapped a portion of the Raditladi quadrangle
(19-358N, 106-1338E) at a regional scale at a resolution of 166 m/pixel. We characterized the
geological context of the area and evaluated the stratigraphic relationships between the units. To
obtain a representative geological section, we analysed and corrected available topographical
data. The geological cross-section derived from our regional mapping suggests that volcanic
emplacement of Raditladi's inner plains followed the topography of the basin after the deposition
of impact-related units (i.e. melts, breccias and rim collapse) and was driven by low-viscosity
flows. Hollows that appear on Raditladi's peak ring were possibly formed from low-reflectance
intercrater plains materials exposed through the peak ring unit.