EGU General Assembly 2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.

A numerical modelling toolbox for identifying the expression of dome-forming volcanism on exoplanets

Claire Harnett1, Michael Heap2, and Mark Thomas3
Claire Harnett et al.
  • 1University College Dublin, School of Earth Sciences, Dublin, Ireland (
  • 2EOST, University of Strasbourg, Strasbourg, France (
  • 3School of Earth and Environmental Science, University of Leeds, UK (

The presence of volcanism is often anecdotally used to define a “living planet”. Since dome-building volcanism on Earth occurs primarily at plate boundaries, the identification of such domes could inform on exoplanetary development. Lava domes form when extruded magma is too viscous to flow from a vent, and their morphology on Earth varies from flat, pancake lobes to steep, blocky domes. Identification of lava domes on other terrestrial planets in our Solar System indicates that they likely also exist on rocky exoplanets. Here we show, using particle-based modelling, that the diversity of lava dome morphology in our Solar System is dwarfed by the diversity expected for exoplanets. Specifically, the height-to-diameter ratio of a dome decreases as a function of increasing gravity (i.e., planetary mass and radius). For example, lava domes on high-gravity super-Earths will be extremely wide and flat and a volcanic origin may not be immediately apparent. Creating a toolbox to help identify exoplanetary volcanism will allow us to make initial estimations as to the development and habitability of these alien worlds as images become available.

How to cite: Harnett, C., Heap, M., and Thomas, M.: A numerical modelling toolbox for identifying the expression of dome-forming volcanism on exoplanets, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-9482,, 2021.

Display materials

Display file

Comments on the display material

to access the discussion