For decades, Mars has been perceived primarily as a planet dominated by basaltic rocks—a relatively monotonous and primitive crust that starkly contrasted with Earth’s varied geological makeup. However, a new wave of research is upending this long-held viewpoint, revealing that the Red Planet’s surface may once have hosted far more complex and evolved rock types than previously recognized. Recent discoveries from both orbital reconnaissance and in situ rover missions have charted a geological history of Mars that includes the development of silica-rich crustal components remarkably similar to some of Earth’s oldest continental formations. At the heart of this emerging story lies a unique Martian meteorite, Northwest Africa (NWA) 7533, whose petrological characteristics are offering unprecedented insights into early Martian differentiation and crust formation processes.
The study of NWA 7533 and its companion meteorites has revealed a geochemical diversity that challenges the simplistic basaltic narrative. These meteorites, classified as regolith breccias, contain lithic clasts that stand out for their unusual mineralogy. Among these clasts, investigators have identified grains of quartz embedded within a granitic matrix dominated by potassium feldspar and plagioclase—minerals typically associated with evolved, silica-rich rocks on Earth. This discovery marks the first clear evidence of quartz-bearing granitic material originating from Mars, signaling that the planet may have developed differentiated crustal rocks at a far earlier stage than previously thought.
The presence of quartz in Martian meteorites is significant because quartz is notably absent from the basaltic and ultramafic rocks commonly found on Mars and in Martian-derived materials. Quartz formation demands specific geochemical pathways and environmental conditions, including sufficient silica saturation and the right thermal regimes, often involving liquid water. By documenting quartz-rich lithologies within NWA 7533 clasts, researchers suggest that the early Martian crust was hydrothermally active and chemically evolved, diverging substantially from the basalt-dominated paradigm.
Moreover, the granitic clasts within NWA 7533 bear a remarkable bulk chemical resemblance to some of Earth’s oldest known rock formations, such as the Acasta gneisses found in Canada, which are over four billion years old. These ancient terrestrial rocks are products of intense crustal differentiation and represent some of the earliest continental crust components on Earth. The parallel between the Martian meteorite and these terrestrial analogs implies that Mars, too, underwent processes capable of generating evolved, felsic rocks early in its history, within the first few hundred million years after planetary formation, during the pre-Noachian era.
Understanding when and how Mars developed such evolved crustal components is crucial to reconstructing its geological and geodynamical evolution. While Mars does not exhibit plate tectonics like Earth, evidence points to alternative processes that could have driven differentiation and crustal melting. The study proposes that the combined mechanisms of hydrothermal activity and impact melting may have played a pivotal role. Large bolide impacts, common during the heavy bombardment period, generated immense heat capable of melting the local crustal material, which when coupled with hydrothermal circulation driven by impact-heated fluids, could facilitate the chemical evolution of primitive basaltic rocks into more silicic, granitic compositions.
This hypothesis is supported by parallels drawn between the geochemical traits of the Martian meteorite clasts and rocks formed within terrestrial large impact structures such as the Sudbury basin in Canada. Sudbury, one of Earth’s largest and oldest known impact sites, hosts granitic rocks formed from the melting and subsequent recrystallization of crustal material under the influence of impact-generated hydrothermal systems. This analogy strengthens the prospect that analogous processes operated on Mars, suggesting a universality of impact-driven crustal evolution during the early solar system.
The implications of these findings extend beyond mineralogy and geodynamics. The co-occurrence of quartz-bearing granitic materials and evidence for water indicates that early Mars hosted the environmental conditions necessary for sustained hydrothermal systems. This has profound ramifications for our understanding of Mars’ early habitability and the possible emergence of life. Hydrothermal environments are well regarded as prime candidates for nurturing prebiotic chemistry on Earth, and the identification of such conditions on Mars considerably broadens the scope for astrobiological potential in the planet’s formative years.
Additionally, the identification of granitic crustal fragments in Martian meteorites helps calibrate the timeline of Mars’ crust development. Prior models often presumed a predominantly basaltic surface throughout much of Mars’ history, with differentiation occurring at surprisingly shallow depths or over protracted timescales. Instead, the evidence from quartz-bearing clasts implies rapid crustal maturation, pointing to dynamic early planetary processes that facilitated the segregation of felsic materials, probably within the first few hundred million years of Mars’ formation, preceding the formation of the heavily cratered Noachian terrains.
The NWA 7533 meteorite thus opens a window into the enigmatic pre-Noachian epoch, a time in Mars’ history that remains one of the least understood. Sampling rocks from this period remains challenging due to the planet’s intense volcanic resurfacing and impact overprinting. Meteorites like NWA 7533, representing fragments of ancient crust ejected by impacts, provide invaluable snapshots into the composition and evolution of early Martian lithologies, circumventing the need for direct in situ sampling, which is currently beyond our reach.
Advances in in situ geochemical techniques, such as laser-ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and electron microprobe analysis, have been pivotal in characterizing the mineral architecture and trace element patterns within these clasts. Detailed petrological studies have unveiled textural relationships, crystallization sequences, and chemical differentiation profiles consistent with an evolved granitic origin, affirming the complexity of early Martian crust-forming processes.
Such refined analytical capabilities have enabled scientists to reconstruct the thermal histories and fluid-rock interactions that likely sculpted Mars’ earliest crustal assemblages. The identification of accessory minerals and elemental fractionations points toward episodic hydrothermal alteration and impact-induced metamorphism, marking a period of geochemical diversification unprecedented for a planet often labelled as cold and dry in its early days.
This burgeoning body of evidence forces a reevaluation of standard Martian geology models and injects new vigor into comparative planetology. The commonalities between early Earth and Mars in crustal evolution highlight potentially universal planetary processes in the inner solar system and stress the importance of impact events and water-mediated alteration in shaping planetary crusts differently from the paradigm of plate tectonics.
Looking forward, these insights strengthen the case for future missions targeting pre-Noachian terrains and returning samples from sites rich in ancient granitic materials. Understanding the prevalence and distribution of such evolved rocks on Mars will help clarify the mechanisms of crustal differentiation and the planetary conditions conducive to habitability. Even more tantalizingly, the recognition of pre-Noachian granitic rocks might hint at the presence of early siliceous sediments and weathering processes, further aligning Mars’ geological past with early Earth analogs.
This study represents a milestone in Martian petrology. For the first time, unequivocal quartz-bearing granitic rocks are traced back to a pre-Noachian era, reshaping our conceptions of Mars’ early crust and environmental conditions. The combined evidence suggests that Mars shared more geological kinship with Earth than previously appreciated, both shaped by the primal interplay of hydrothermal systems and impacts that seeded the rise of complex crustal architectures.
In summary, the quartz-rich granitic clasts found in meteorite NWA 7533 redefine Mars from an inert basaltic planet to one that, at least in its infancy, harbored dynamic, water-rich environments capable of producing evolved crustal rocks. These findings not only illuminate Mars’ geological past but also open new avenues for exploring how planets differentiate and develop the ingredients potentially necessary for life.
Subject of Research: Evidence of pre-Noachian granitic rocks on Mars and insights into early Martian crustal differentiation processes.
Article Title: Evidence for pre-Noachian granitic rocks on Mars from quartz in meteorite NWA 7533.
Article References:
Malarewicz, V., Beyssac, O., Zanda, B. et al. Evidence for pre-Noachian granitic rocks on Mars from quartz in meteorite NWA 7533. Nat. Geosci. 18, 207–212 (2025). https://doi.org/10.1038/s41561-025-01653-z
Image Credits: AI Generated
