New Morphometric Data of Lunar Sinuous Rilles

Abstract

On the surface of the Moon a large number of linear features are recognizable. Long and narrow depressions are defined as lunar rilles. Their morphology has different characteristics, related to their origin. Among these, the sinuous rilles represent lineaments considered remnants of shallow lava channels. In this article, a quadrant of the Moon has been analyzed to recognize and map this type of morphology. An accurate morphometric analysis has been accomplished, using the lunar reconnaissance orbiter camera which has a resolution of 100 m/pixel, and the digital elevation model from lunar orbiter laser altimeter with a resolution of 6 m/pixel. A total of 51 sinuous rilles have been recognized in the study area, 18 of which are new, improving a previous catalogue. The resulting quantitative and qualitative measurements were analyze and compared each other’ to identify potential morphological trends. Different relationships between morphological parameters have been proposed, and the results enhance the importance of substrate composition in the evolution of these features, emerged mainly from the variations in width and depth values. The linear relationship between these two parameters is consistent with the idea that erosion efficiency acts proportionally in both vertical and horizontal directions. Partial filling phenomena by subsequent lava flows probably occurred in some sinuous rilles located in maria. The hypothesis of a constructive genesis requires further investigation to identify the levees created by sinuous rilles’ formation process.