Complex geomorphologic assemblage of terrains in association with the banded terrain in Hellas basin, Mars

Hellas basin acts as a major sink for the southern highlands of Mars and is likely to have recorded several episodes of sedimentation and erosion. The north-western part of the basin displays a potentially unique Amazonian landscape domain in the deepest part of Hellas, called “banded terrain”, which is a deposit characterized by an alternation of narrow band shapes and inter-bands displaying a sinuous and relatively smooth surface texture suggesting a viscous flow origin. Here we use high-resolution (HiRISE and CTX) images to assess the geomorphological interaction of the banded terrain with the surrounding geomorphologic domains in the NW interior of Hellas to gain a better understanding of the geological evolution of the region as a whole. Our analysis reveals that the banded terrain is associated with six geomorphologic domains: a central plateau named Alpheus Colles, plain deposits (P1 and P2), reticulate (RT1 and RT2) and honeycomb terrains. Based on the analysis of the geomorphology of these domains and their cross-cutting relationships, we show that no widespread deposition post-dates the formation of the banded terrain, which implies that this domain is the youngest and latest deposit of the interior of Hellas. Therefore, the level of geologic activity in the NW Hellas during the Amazonian appears to have been relatively low and restricted to modification of the landscape through mechanical weathering, aeolian and periglacial processes. Thermophysical data and cross-cutting relationships support hypotheses of modification of the honeycomb terrain via vertical rise of diapirs such as ice diapirism, and the formation of the plain deposits through deposition and remobilization of an ice-rich mantle deposit. Finally, the observed gradual transition between honeycomb and banded terrain suggests that the banded terrain may have covered a larger area of the NW interior of Hellas in the past than previously thought. This has implications on the understanding of the evolution of the deepest part of Hellas.

Les terrains secondaires des environs de Tiaret et de Frenda (Département d'Oran, Algérie) Propositions données par la Faculté.

Thése--Paris.

Les montagnes entre Briançon et Vallouise (écailles briançonnaises, terrains cristallins de l'Eychauda, massif de Pierre-Eyrautz, etc.),

At head of title: Ministère des travaux publics.

Mode et conditions des ventes des terrains du Chateau-Trompette, en exécution de lʹordonnance du Roi, du 26 septembre 1819.

At head of title: Mairie de la ville de Bordeaux.

Observations sur la motion faite à l'Assemblé des Cent-Trente, relativement à la propriété des terrains du Château Trompette.

Caption title.

Description de coquilles caratéristiques des terrains

Mode of access: Internet.

Description des mollusques et rayonnés fossiles: terrains crétacés /

Incluye índice.

Mémoire sur les terrains de sédiment superieurs calcaréo-trappéens du Vicentin et sur quelques terrains d'Italie, de France, d'Allemagne, etc., qui peuvent se rapporter a la même époque /

Mode of access: Internet.

Premières notions de géologie (pierres et terrains)

p. 317-320, advertising matter.

Élémens pratiques d'exploitation, contenant tout ce qui est relatif à l'art d'explorer la surface des terrains, d'y faire des travaux de recherche et d'y établir des exploitations réglées; la description des moyens employés pour l'extraction et le transport souterrain des minerais et des combustibles; les diverses méthodes de boiser, murailler, aérer et assécher les mines; les secours à donner aux noyés, asphyxiés et brulés; des notions sur l'administration, la comptabilité, etc., etc.

Mode of access: Internet.