From a report submitted to the Endowment Committee by Hely Cristian Branco, Curtin University.
The project’s main goal was to investigate the thermal evolution of Mars and Venus through integrating shock physics simulations of impacts made using iSALE2D and thermal evolution models made with GAIA. This was carried out in the form of a short-term research stay at the German Aerospace Center (DLR) in Berlin, as access to the latest version of GAIA is restricted to members of the institution.
The investigation consisted in comparing the effects of impact-induced thermal anomalies calculated using iSALE (a more realistic approach, which considers target material properties and a more accurate anomaly geometry) and classical scaling relationships (which assume a homogeneous target and spherical anomaly geometry). Classical scaling relationships are incorporated into GAIA and can be used as an optional module by its users. The use of thermal anomalies calculated using iSALE requires processing iSALE outputs and converting the data to a format compatible with GAIA. To some extend this was done in the past (e.g. Bjonnes et al. 2021), but no stablished computational routine or method were available.
During my stay in Berlin, we developed a method to extract thermal anomalies from iSALE simulations and import them to GAIA. The method can be easily replicated and applied to any planetary object such as Venus and Mars given that sufficient information is available to perform the shock physics simulations in the first place. Preliminary results for Mars indicate that the geometry and temperature distribution of thermal anomalies calculated by iSALE and by classical scaling are significantly different and affect the thermal evolution of large impact structures. Early modelling of Hellas, Isidis and Utopia impact basins show differences in the final thermal gradients and subsurface temperature distribution of the structures when using the two types of thermal anomalies.
More precise models of the referred impact basins on Mars and of large impact structures on Venus are being developed and are expected to be ready in the second semester of 2025. This method is of great interest to the community, as iSALE and GAIA are often used in isolation.
The Meteoritical Society funds were used to support my stay in Berlin for three months while the integration between iSALE and GAIA was being developed. The funds were used towards living expenses, as detailed in the funding summary.