Évènements

Présentation des résultats préliminaire de la double datation (U-Th)/He – U/Pb sur les sédiments passés et moderne de la rivière Congo

Metal-enhanced phosphorylation on primitive planetary surfaces: Geological and Experimental perspectives
amphithéâtre du CRPG

(amphithéâtre du CRPG)

Accurate dating of Quaternary fluvial archives is critical: spatio-temporal patterns of river incision unfold uplift history of the Variscan Rhenish/Ardenne Massif (N. Europe)

Résumé: The Rhenish/Ardenne Massif experienced significant intraplate uplift during the Plio-Quaternary, but its timing, rates, and driving mechanisms have long remained debated due to limited chronological control. Recent dating of fluvial terraces and cave levels using cosmogenic nuclides, ESR, and luminescence methods now provides more robust age constraints. Compiled data, along with new age results, reveal a massif-wide peak in river incision during the Early to Middle Pleistocene, with a notable time lag between the southeastern and northwestern margins. Earlier incision along the Rhine–Moselle system compared to the Meuse supports the idea of a northward-migrating uplift wave driven by regional tectonic stresses linked to the Alps.

Détection 3D d’assemblages minéralogiques par SR-μXCT dans un échantillon de l’astéroïde Ryugu : étude multi-analytique de leur formation et évolution
amphithéâtre du CRPG

THE VOYAGE OF WATER AND ORGANICS FROM THE INTERSTELLAR MEDIUM TO THE SOLAR SYSTEM

The Solar System was born about 4.5 Byr ago from a cloud of gas and dust after a long and complex process, whose principal phases are nowadays identified but whose many details are still debated. In this presentation, I will review what is known about the water and organics that formed in the interstellar medium and presumably reached, in a way or another, Earth and the inner rocky planets of the Solar System. Specifically, I will focus on our knowledge based on the most recent studies of solar-type planetary systems at present forming in the Milky Way.

• Yanou Crenne (encadrée par Annachiara Bartolini et Guillaume Paris) – Impact of the Toba super-eruptions in the Indian Ocean: biogeochemical responses and implications for planktonic foraminiferal calcification
• Eve Guillemin (encadrée par Camille Cartier et François Faure) – Origin of aubrites and their parent bodie(s) : a petrological, geochemical and cosmochemical study

Increasing temperatures controlled rockfall activity in the Rwenzori Mountains (Uganda) over the past 11,000 years

Coevolution of crustal maturation and surface environments based on the triple oxygen isotope records of surface archives

Abstract: Sometimes during the Archean, Earth shifted from an early “water world” to a hypsometrically bimodal planet, where subaerial continents emerged. The available sedimentological record of shales, glacial diamictites, and detrital zircon provides isotopic and petrological insights showing that the crust was becoming more silicic and exposed as it evolved over time, primarily driven by planetary cooling and the start of horizontal tectonics. The critical tipping point of emergence was reached at the end of the Archean with the formation of the first supercontinent. Exposed large swaths of subaerial crust, initiated surface weathering as an important new geochemical flux regulating climate, and influenced the proliferation of lifeforms on early Earth via habitat creation.

Satellites et modèles climatiques au service des pôles : des plateformes de glace en Antarctique aux projections climatiques au Groenland