TECTONIC AND MORPHOLOGIC ANALYSIS OF WRINKLE RIDGES ON MARS

Abstract

The history of Martian strain is captured and recorded through compressional wrinkle ridges. Wrinkle ridges or analogues of these ridges exist on every terrestrial planet. This study analyzes the morphology and characteristics of Martian wrinkle ridges, using topographic analysis. The morphological interpretation focuses on two populations of ridges found in the smooth volcanic plains of Solis and Lunae Plana. Our study confirms wrinkle ridges have four distinct morphologies: symmetric, asymmetric, double, and, less commonly, arch. With this, commonalities in their total height, width, length, orientation, and step between one side of the fault and the other, were observed. In comparison to Solis and Lunae, Hesperia Planum and Chryse Planitia were studied in order to determine if wrinkle ridge characteristics are affected by the thickness of the crust or the thickness of the volcanic plains. A displacement length ratio was used to calculate total shortening and strain was determined using ridge lengths, and this shortening. Areas with a thick lava layer and thick crust present had the highest strain, however, not a clear relationship could be determined.Wrinkle ridges are present in the smooth volcanic plains of Hesperian age as well as old, heavily cratered Noachian terrain. Our analysis examines the distribution of wrinkle ridge populations across these different surfaces of Mars. It supports a lower strain in the Noachian surfaces than found in the Hesperian aged surfaces. These structures are important for future analyses of strain and geodynamics on Mars.