Separation of quasi-continuous and periodic components of lineament formation at the Belus – Phoenix - Rhadamanthys Linea “triangle” on Europa

Abstract

The first images of Jupiter's moon Europa from the Voyager missions sparked the curiosity about the lineament system appearing at the surface. Curiosity quickly turned into profound interest, following the discovery of its subsurface ocean, which may harbour life below the thick ice crust. This study revisits Europa and reinvestigates its surface using high-resolution Galileo data and mapping one of its most characteristic surface patterns: the complex network of lineaments. The analysis of the morphological type of over two hundred lineaments and their crosscutting relationship based on relative age indicate the influence of cyclical tidal force, orbital forcing, and the nonsynchronous rotation triggered periodic stress in the formation of three characteristic lineaments-generations, along with additional and unaccounted forces that may contribute to surface renewal. Despite ongoing debate, which suggests that Earth-like tectonism (e.g., subduction) is less likely plausible on Europa, the result of this study calls for some process acting along with tidal forces, causing shortening, horizontal movement and increasing extension in the ice plate located in the region of a suspected subduction (or low-relief subsumption) zone and may be part of the “subducting” crust. This study raises new questions and encourages additional scientific discussions, which, along with the Europa Clipper and JUICE missions, will help to understand the nature of Europa's ocean and ice-tectonic processes.