Formation of mountains on Io: Variable volcanism and thermal stresses

Spatial distribution of volcanoes on Io: Implications for tidal heating and magma ascent

“…Regions of enhanced volcanism may therefore be related to preferred pathways to the surface rather than directly correlated with sites of maximum heat production. Anisotropies controlling the locations of magma upwelling and enhanced volcanism may include existing fault distributions in the lithosphere and the combination of stresses associated with mantle convection, magma diapirism, magma chambers, shallow intrusions, volcanic conduits, volcanic edifices, mountains, and tidal flexing (McKinnon et al, 2001;Kirchoff and McKinnon, 2009;Kirchoff et al, 2011). However, the existence of global magma ocean (Khurana et al, 2011) Tackley, P.J., Schubert, G., Schenk, P., Ratcliff, J.T., Matas, J.-P., 2001.…”

Tectonics of the outer planet satellites

“…On Io, this could be the result of construction of volcanic edifices or global convection patterns forming localized sites of upwelling and downwelling (e.g., Tackley et al, 2001). However, constructional volcanic edifices are quite rare on Io (Schenk et al, 2004a) and convective stresses on Io are likely to be quite small (Kirchoff and McKinnon, 2009). On Io, constant global resurfacing by lavas and deposition from volcanic plumes can locally erase tectonic patterns of this sort, in part or entirely.…”

Ferrovolcanism: Iron Volcanism on Metallic Asteroids

“…Solid material tends to delaminate from the crust because it is more dense than the melt immediately below it, and at the base of the crust temperatures are high enough, and thus viscosities low enough, for material to flow. Delamination has been discussed on Io (Kirchoff & McKinnon, 2009), as well as on metallic asteroids (Neufeld et al, 2019), and in the latter case is expected to recur on timescales of a few tens of kiloyears. The stress will vary in and around the diapir, but Kirchoff and McKinnon (2009) point out that its magnitude is roughly ∼ Δ g where is the thickness of the layer being shed.…”