Experimental investigation of Fe-clay/organic interactions under asteroidal conditions

Carbonaceous chondrites contain both soluble and insoluble organic materials (SOM IOM) which may have been produced in different environments via processes or share possible genetic relationships. The SOM from IOM during hydrothermal episodes on asteroids, vice versa. potential role played by the mineral matrix these (clay minerals of variable crystallinity) remains to be constrained. Here, we exposed a mixture formaldehyde glycolaldehyde with ammonia-bearing liquid water together Fe-rich smectitic conditions mimicking asteroidal conditions. We used amorphous gel smectite crystalline smectites order understand influence crystallinity evolution OM. organo-mineral experimental residues were characterized at multiple length scales using X-ray diffraction microscopy/spectroscopic tools. Results evidence that some polymerizes/condenses absence smectites. Yet, presence inhibits this production IOM. Indeed, interactions between clay surfaces (interlayers edges) reduce concentration available for polymerization/condensation reactions, necessary step In addition, OM disorganizes crystallization silicates, leading smaller crystal sized particles exhibiting lower permanent charge. This might suggests charge distribution help better constraining origin chondritic minerals. Altogether, present study sheds new light having occurred onto/within asteroids. formation OM-rich aqueous fluids does not occur alteration silicates. would mean is either within pockets free initially accreted as IOM-rich grain. Last, about ?50 wt% initial C could removed end experiments classical solvent extraction protocols, demonstrating high fraction carbonaceous overlooked.