Research project IM/RT/23/ULTIMO (Research action IM)
The Antarctic environment represents one of the last frontiers in scientific exploration. For more than 10 years, the VUB-ULB-RBINS-NIPR consortium has focused on constraining the origin and evolution of both rocks (terrestrial and extraterrestrial [ET]) and ice in proximity of the Belgian Princess Elisabeth station (PEA) in the Sør Rondane Mountains (SRM) by applying a highly interdisciplinary approach. This methodology has led to the recovery of more than 1,300 meteorites from blue ice fields, the retrieval of ~50,000 microscopic ET particles from high-altitude sedimentary deposits (including micrometeorites, airburst debris and impact ejecta), as well as determining the geological and exposure histories of rock outcrops, moraines, and ice in this area.
Together, the rock and ice samples have unlocked an astonishing treasure of information on the origin of the Solar System, the formation of planets, past climatological conditions, as well as the formation and exposure of regional geological and glaciological features (e.g., [1-5]). The time has now come to expand the activities of our consortium to the Belgica Mountains, of which the scientific potential remains largely untapped to date. This isolated mountain chain about 16 km long is located ~100 km east-southeast of the SRM. It was named by the Belgian Antarctic Expedition in 1957-1958 under G. de Gerlache, and only the northern range of this mountain chain was revisited once during a Japanese Antarctic Research Expedition (JARE) in 1998, with an excellent success rate for finding meteorites in a short amount of time (37 meteorites recovered over a 3-day time period).
The aims of the ULTIMO project are to (1) validate the predictive power of existing machine learning approaches to trace meteorite accumulation in the Antarctic environment [5] and subsequently collect and characterize meteorites in that blue ice field area, (2) substantially expand the current inventory of ET particles and cosmic events by sampling deposits in the previously unexplored territory of the Belgica Mountains and compare the physicochemical properties of the sampled deposits and extracted particles to those of existing collections to learn about the early evolution of the Solar System, (3) determine the potential of the blue ice fields surrounding the Belgica Mountains to host ancient ice by mapping spatiotemporal variations using stable isotope variations (δ18O en δD), directly measuring the age of the surface ice, and modelling the local ice flow, and (4) study the geological and exposure history of the Belgica Mountains bedrock and associated moraines.
The study of unique cosmic material allows to define source regions in the Solar System from where the material that arrives on Earth today derives and to detect possible changes in the intensity and nature of the ET flux over the last few million years (Myr). As such, this ET material complements costly sample-return missions to primitive asteroids and comets and allows to explore the very first stages in the evolution of the protoplanetary disk using material accessible here on Earth. Notably, meteorites and micrometeorites (and other microscopic traces of ET events) can highlight different processes and reservoirs, as – due to their sizes – the latter undergo different preservation biases. Similarly, the exposure histories of ice and bedrock can be used in conjunction to refine existing tectonic, geomorphological, glacioeustatic, and paleoenvironmental reconstructions and models, which are critical in Antarctica as the geological bedrock is covered by ice. The targeted collections and resulting scientific insights further enhance the position of this Belgium-led international consortium at the vanguard of the geological, planetary, and paleoclimatic sciences.
[1] Imae N. et al. 2015. Antarct. Rec. 59, 38-71; [2] Zekollari H. et al. 2019. Geochim. Cosmochim. Ac. 248, 289-310. [3] Goderis S. et al. 2020. Geochim. Cosmochim. Ac. 270, 112-143; [4] van Ginneken M. et al. 2021. Sci. Adv. 7, eabc1008. [5] Tollenaar V. J. W. et al. 2022. Sci. Adv. 8, eabj8138.
