3D Digital Outcrop Model reconstruction of the Kimberley outcrop (Gale crater, Mars) and its integration into Virtual Reality for simulated geological analysis

Gwénaël Caravaca (1) , Stéphane Le Mouélic (1) , Nicolas Mangold (1) , Jonas L'Haridon (2) , Laetitia Le Deit (1) , Marion Massé (1)

1 LPG - Laboratoire de Planétologie et Géodynamique [UMR 6112]
2 ESF - European Science Foundation

Structure-from-Motion photogrammetry has recently become a cheap and efficient method to reconstruct accurateand highly-resolved 3D Digital Outcrop Model (DOM) from a single set of images. This enables the 3D visualizationof hardly accessible and/or remote geological scenes, which is of strong interest for planetary bodies.This paper focuses on the reconstruction of the DOM of the Kimberley outcrop (Gale crater, Mars) using the AgisoftPhotoScan Professional software. This software is used to compute an accurate, scaled and georeferenced3D mesh of this outcrop from set of multi-scale images taken by the Mars Science Laboratory rover Curiosity.This model was merged with a 3D model computed from orbital images from the High Resolution Imaging ScienceExperiment camera (HiRISE) to provide the context. One of the challenges is to integrate data coming fromdifferent cameras (with varying optical parameters) not specifically designed for 3D rendering, and with limitedpoints of views. While the obtained DOM allows to observe and characterize geological features of Kimberley'ssedimentary series, classic viewing methods through a 2D screen limits the understanding of the real 3D geometryand scale of the outcrop, as there is no feature such as trees or roads on Mars to provide size references tothe user. To overcome this issue and facilitate the interpretation of the DOM, the latter is integrated into a VirtualReality (VR) environment that enables one or several users working in a collaborative mode to experiencea real scale, reliable and realistic depiction of the actual geometries of the geological features reconstructed onthe mesh. Precise and accurate description, contextualization of the samplings and mapping of the Kimberleyoutcrop can therefore be achieved in VR allowing for more precise characterization and interpretations, the sameway one would do on a real geological field trip.

Mots clés: Mars; Curiosity; Virtual reality; Geological mapping; Digital outcrop model; Gale crater

Domaines: Sciences de la Terre; Planétologie; Stratigraphie

Gwénaël Caravaca, Stéphane Le Mouélic, Nicolas Mangold, Jonas L'Haridon, Laetitia Le Deit, et al.. 3D Digital Outcrop Model reconstruction of the Kimberley outcrop (Gale crater, Mars) and its integration into Virtual Reality for simulated geological analysis. Planetary and Space Science, 2020, 182, pp.104808. ⟨10.1016/j.pss.2019.104808⟩. ⟨hal-02386944⟩