A GEOLOGIC MAP OF THE DAVINCI PROBE DESCENT IMAGING CORRIDOR AND TOUCHDOWN ZONE: ALPHA REGIO, VENUS (Invited Presentation)

Through the NASA Discovery Program and NASA Goddard Space Flight Center, the Deep Atmosphere Venus Investigation of Noble gases, Chemistry, and Imaging (DAVINCI) mission will help address questions we have about the evolution of the atmosphere and surface on Venus. The mission is designed to complete two flybys for remote sensing objectives before releasing a descent sphere (or probe) over the Alpha Regio tessera region. The Venus Descent Imager (VenDI) camera onboard the descent probe will image the surface of Venus below the clouds at sub- m/pixel resolution in two NIR channels (0.74-1.03 μm and 0.98-1.03 μm). This is a greater resolution than the currently available Magellan Synthetic Aperture Radar (SAR) imagery at ~100 m resolution. In preparation for the descent, we have produced a high-resolution geologic map (1:600,000 map scale) of the DAVINCI probe touchdown zone.

Ten geologic units and four types of structures (i.e., ridges, troughs, graben, and lineaments) are mapped throughout the entire study area. The oldest units preserve structural evidence of compressional ridges followed by extensional graben supporting models of tesserae formation via downwelling. The number and density of the structures decreases with stratigraphic age indicating waning deformation. More than half of the study area consists of plains materials interpreted to be volcanic. We identify evidence of mass wasting and pervasive lineaments of unknown origin across the descent region. The number and types of units in this full-resolution Magellan geologic map of the target descent site reveals a complex history which may expand our traditional definition of the “tessera terrain”. The VenDI images will validate mapping of small-scale features in radar, and address questions about the surface morphology and composition of the tesserae materials.