COPRATES CHASMA NORTH WALL INTERIOR LAYERED DEPOSIT: LAYER MEASUREMENTS AND COMPARISON WITH JUVENTAE CHASMA ILDS USING MARS EXPRESS HIGH RESOLUTION STEREO CAMERA (HRSC) DERIVED TOPOGRAPHY Michael, G.1, E. Hauber1, K. Gwinner1, R. Stesky2, F. Fueten3, D. Reiss1, H. Hoffmann1, R. Jaumann1, G. Neukum4, T. Zegers5, and the HRSC Co-Investigator Team 1Institute of Planetary Research, German Aerospace Center (DLR), Berlin, Germany 2Pangaea Scientific, Brockville, Ontario, Canada 3Department of Earth Sciences, Brock University, St. Catharines, Ontario, Canada 4Remote Sensing of the Earth and Planets, Freie Universitaet, Berlin, Germany 5ESTEC, ESA, Noordwijk, The Netherlands Introduction: The interior layered deposit (ILD) in the north wall of Coprates Chasma differs from those we have examined in Hebes, Ophir, Candor, Melas, and Juventae Chasmata [1] in that its base apparently occurs some 2700 m above the main chasma floor. Situated in a re-entrant of the chasma wall, it has two main sections, the maximum lateral extent of the larger deposit being about 15 km. Nevertheless, it displays several small-scale features in common with an apparently exhumed ILD in Juventae Chasma (HRSC orbit 1070) of much greater extent (50-150 km, also in two sections): bright material; regular layering with 3-6 m layer thickness; steeper slopes with chutes headed by scalloped alcoves, and ending with dark talus fans; morphologically similar yardangs. Using a digital terrain model derived from HRSC stereo together with projected nadir and colour channels and manually coregistered MOC images, we investigate the structure of the layering, and the present erosional features. As elsewhere, we are interested to make measurements of the strike and dip of the layering, since this information could potentially discriminate between theories of the origin of the layers: whether water emplaced sediments, volcanic ash deposits, or some other airfall deposit. Coprates floor, and has a height of ~3000m. It shows two apparent scales of layering: one producing a step-like relief, the other much finer. Measurements of the fine layers give mean thickness values of 3.2 m (Profile 1: 30 layers in 205m over 1.5km baseline, registered MOC, only dark to light transitions counted) and 5.7 m (Profile 2: 45 layers in 255m over 1.6km baseline). The coarser layers are measured to have a mean thickness of 85m (Profile 3: 14 layers in 1200m over 3 km baseline). Seen in perspective view with MOC overlays, it would appear that the coarse layering is not horizontal, but dips outward from the centre of the ILD. Wind eroded yardangs are seen between two main sections in apparently similar material. Talus deposits originate particularly from one height level in the main section. Some appear dark and fresh; lighter ones more eroded. Their formation leaves distinctive alcoves at the head of a chute. At the south-west of the ILD there is a scarp of 60є inclination with many such chutes, and morphologically similar to that seen in the Juventae North ILD. The lesser section of the ILD is confined by a ridge of the chasma wall.