142-4 Fracture-Controlled Alteration in Igneous Terrains: Implications for Microbial Habitability on Mars

Session: Geomorphology and Landscape Evolution of Mars (Posters)

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Volcanic and intrusive igneous systems create fractures that act as pathways for heat and mineral-rich fluids, producing alteration zones that can support microbial life. On Earth, these environments develop dike margins, intrusive contacts, and hydrothermal systems where fluid-rock interactions alter mineralogy and generate chemically favorable conditions for microbial communities. These similar volcanic and tectonic processes occurred throughout Martian history and may have produced environments capable of supporting life while preserving evidence of past biological activity. Understanding how these systems develop can be detected remotely is important for identifying future astrobiological exploration locations.

This study investigates fracture-controlled alteration systems in connection with igneous intrusions in the southwestern United States as terrestrial analogs for Mars. Field sites include well-exposed dike swarms, volcanic vents, contact alteration, and evidence of fluid migration. An integrated approach combining multispectral remote sensing, uncrewed aerial system photogrammetry, geologic mapping, and ground-based magnetometry is used to characterize alteration patterns and identify potential microbial habitats. These datasets are supplemented by rock magnetic, mineralogical, and microbial analyses to look at relationships between fracture systems, fluid pathways, mineral alteration, and biologically influenced environments.

Magnetic anomalies associated with iron oxides and alteration minerals are examined alongside visible and near-infrared spectral signatures to determine whether remote sensing techniques can reliably identify environments favorable for microbial colonization. A Raman spectrometer is used to characterize mineralogical compositions and identify potential biosignature-bearing phases within alteration zones, providing complementary information to remote sensing observations. Attention is given to intrusion-host rock contacts and alteration locations where mineral precipitation, fluid circulation, and geochemical gradients may enhance habitability and biosignature preservation. These environments provide opportunities to evaluate how biological and geological processes interact to produce detectable signatures in volcanic terrains. Similar fracture associated alteration zones have become important for planetary exploration because they may preserve evidence of past habitable conditions and serve as targets for future missions.

By comparing terrestrial fracture-controlled alteration systems with volcanic and tectonic features observed on Mars, this research is used to improve interpretation of Martian alteration zones and developing strategies for identifying future exploration targets. Results can contribute to ongoing efforts in planetary geology, geomicrobiology, andastrobiology by increasing our understanding of how volcanic systems may create and preserve habitable environments on rocky planets.

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