¹Arka Pratim Chatterjee, ²Meredith Townsend, ³Christian Huber, ³James W. Head III, ¹Olivier Bachmann
Earth and Planetary Science Letters 681, 119948 Open Access Link to Article [https://doi.org/10.1016/j.epsl.2026.119948]
¹Institute for Geochemistry and Petrology, Department of Earth Sciences, ETH Zürich, Switzerland
²Department of Earth and Environmental Sciences, Lehigh University, Bethlehem, PA, USA
³Department of Earth, Environmental, and Planetary Science, Brown University, Providence, RI, USA
Copyright Elsevier

Martian volcanism exhibits two key global trends: magmas evolved from alkali- and silica-rich compositions in the Noachian epoch to alkali depleted mafic compositions in the Amazonian, while spatially, young (Amazonian) volcanic resurfacing is confined to the Northern hemisphere and the Tharsis region, with no evidence of recent volcanism in the Southern highlands. A unifying model linking these observations has been lacking. Here, we investigate the relationship between spatio-temporal variations in volcanic resurfacing and the evolution of magma chemistry throughout martian geological history. By analyzing the physical conditions required for volcanic eruptions to be sourced from magma reservoirs located within the martian crust, we model how these conditions influence mantle-derived magma compositions. Our results show that dike propagation from magma chambers is controlled by crustal rheology, with dike height depending on chamber size, magma overpressure, and volatile exsolution (both in the reservoir and within the dike). During the Noachian, the thin crust allowed eruptions of both low- and high-degree mantle melts, consistent with the diverse alkalinity of ancient surface rocks. In contrast, the thickened Amazonian crust selectively filtered low-degree melts, necessitating high recharge rates in large magma reservoirs for eruptions. This filtering effect explains the alkali – depleted compositions of Amazonian basalts, as only high-degree melts could reach the surface. Our study provides a holistic framework connecting magma reservoir dynamics, crustal evolution, and the observed geochemical and spatio-temporal trends in martian volcanism.

^1,2,3Yong Wang et al. (>10)
Earth and Planetary Science Letters 681, 119952 Link to Article [https://doi.org/10.1016/j.epsl.2026.119952]
¹State Key Laboratory of Deep Earth Processes and Resources, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
²YU-CUGW Joint Research Center on Deep Earth and Surface Dynamic Coupling, College of Resources and Environment, Yangtze University, Wuhan 430100, China
³College of Earth and Planetary Science, University of Chinese Academy of Sciences, Beijing 100049, China
Copyright Elsevier

The origin of lunar water—whether inherited during its formation (endogenous) or delivered later (exogenous)—remains a fundamental question in planetary science. Previous studies relying on hydrous minerals or melt inclusions are often compromised by post-magmatic processes. Zircon, with robust physico-chemical stability, serves as a superior archive for preserving primary magmatic composition. Here, we report the first SIMS measurements of water content and hydrogen isotopes in a ca.∼4.38 Ga zircon from lunar meteorite NWA 10049. The zircon exhibits a distinct core-rim structure with anomalous H2O-δD compositions: while the core maintains relatively homogeneous water content (735 to 1164 μg/g) with elevated δD (+1320 to +1882‰), the rim displays variable and inversely correlated water content (879 to 4268 μg/g) and δD (+1879 to +250‰). Such H2O-δD systematics—combined with geochemical and petrological signatures—precludes magmatic degassing or post-magmatic alteration. Instead, we attribute these variations to magma mixing and the subsequent assimilation of heterogeneous exogenous hydrous materials within a massive impact melt sheet. Our findings provide key evidence for the accretion of meteoritic material into the lunar interior before 4.38 Ga, which delivered substantial amounts of water and likely played a critical role in shaping the composition and spatial distribution of volatiles in the early Moon.