2D Dynamics of a lava flow on Europa

Planetary volcanism is a widespread phenomenon throughout the Solar System (Lopes et al., 2010). Volcanism can be classified into two categories: silicate-based volcanism, which occurs on telluric planets, and cryovolcanism, which may occur on several outer Solar System bodies (e.g., Geissler, 2015). Cryovolcanism is assumed to play a significant role in shaping the surfaces of many icy worlds. Evidence of cryovolcanic activity has been detected on Pluto (Singer et al., 2022) and Enceladus (Hansen et al., 2006); it is also suspected of being present on Europa (Fagents, 2003; Sparks et al., 2017) and Titan (Lopes et al., 2013).

Modeling cryovolcanism is crucial for understanding the geological processes shaping the complex surface of Europa. In addition, investigating the resurfacing processes on this moon can improve our insight into subsurface chemophysical properties and prebiotic potential.

Several numerical models of Europa cryovolcanism are already available in the literature, concerning either the possible eruption mechanisms (Lesage, Massol, and Schmidt, 2020) or the subsequent lava flow (Morrison, Whittington, and Mitchell, 2023). According to the scenario we have adopted, liquid water ascending to the surface through the volcanic conduit is significantly depressurized, resulting in a relatively dense mixture of vapor and small ice crystals, similar to terrestrial fluidized snow. This type of fluid has been recognized as having Bingham-like rheology (Maeno and Nishimura, 1979). We then developed a two-dimensional numerical model of the dynamics of such a fluid. We adopted a Smoothed-Particle Hydrodynamics (SPH) method (Gingold and Monaghan, 1977; Lucy, 1977), which is particularly relevant for systems with free surfaces. This makes SPH particularly relevant in the context of lava flow simulations (Prakash and Cleary, 2011; Bilotta et al., 2016).

Focusing on the formation of so-called smooth plains, we have simulated the dynamics of possible effusive eruptions at the surface of Europa. In particular, we assess the influence of parameters governing the thermodynamic and rheological properties of the considered fluid.