Crust-atmosphere coupling and CO 2 sequestration on Mars

1. Crust-atmosphere coupling and CO2 sequestration on Mars Adrienne Macartney (a.macartney.1@research.gla.ac.uk) School of Geographical & Earth Sciences Warm wet Mars? Fluctuating states of equilibrium? Cold icy Mars? Modern Mars What caused the loss of the Mars atmosphere and hydrosphere? • Investigating the role and scale of mineral carbonation via terrestrial analogues (ophiolites), chambered experiments and meteorite analysis. • Geology and engineering cross discipline project building an ultra-sonic rock polishing tool to discover insitu carbonation evidence on Mars.

2. Carbonation Triangle • Exposed ultra-basic rocks • CO2 • Water

3. Hyper - Carbonation Square • Exposed ultra-basic rocks • CO2 • Water • Heat, 180°C optimal

4. Conceptual graph of carbonation dynamics (no units) Joys of Norwegian fieldwork in January Global carbon sequestration Noachian - Hesperian Amazonian Time Micro-carbonation SNC Mars Meteorites Shergottites Nakhlites Chassignites • Wide geographic scale • Low water:rock ratio • Relatively small amounts of sequestration • ‘SNC’ style carbonate evidence

5. Conceptual graph of carbonation dynamics (no units) Joys of Norwegian fieldwork in January Blue = micro-carbonation Red = punctuated hyper-carbonation Global carbon sequestration Noachian - Hesperian Amazonian Time Micro-carbonation Punctuated hyper-carbonation • Wide geographic scale • Low water:rock ratio • Relatively small amounts of sequestration • ‘SNC’ style carbonate evidence • Highly geographically localised • High water:rock ratio required • Significant sequestration • Deep sub-surface, density change, mineralogical evidence

6. Testing micro-carbonation 1 Lafayette Mars meteorite data • ALH 84001 studies to follow shortly • Comparison with terrestrial Ophiolite weathering and replacement sequences (LOC and Oman)

7. Testing micro-carbonation 2 Joys of Norwegian fieldwork in January

8. Testing micro-carbonation 2 Joys of fieldwork in January Leka possesses the full ‘textbook’ sequence of ophiolite strata

9. Testing micro-carbonation 2 The Leka Ophiolite Complex (LOC), Norway • Formed ~497Ma +/- 2Ma, part of the Skei group obducted in the Caledonian orogeny • Analogous to Mars mineral carbon sequestration? • Is the water:rock ratio analogous?

10. Testing micro-carbonation 2 • Initial light microscopy: • Extensive serpentinisation and antigorite replacement • Numerous opaque minerals (chromite, magnetite) • Minor carbonates in veins

11. Testing micro-carbonation 3 Prototyping an improved Mars rover tool RAT - Rock Abrasion Tool MOUSE – Micro-Optic Ultra-Sonic Exfoliator Supported by: Space Glasgow, University of Glasgow Ultra-Sonic Planetary Drilling Team Pfeiffer

12. Summary Water on the Mars surface requires an atmosphere many bars higher than present Mineral carbon sequestration is a robust partial answer, supported by terrestrial analogues - Large scale surface micro-carbonation - Localised punctuated hyper-carbonation (CARBFIX analogue) 3. Comparative microscopic analysis between ophiolites and SNC meteorites may provide insight into important fluid and carbon sequestration processes on the Martian crust-atmosphere 4. Developing the MOUSE, a rover prototype ultra-sonic polisher to aid locating insitu evidence of carbon sequestration