Type IV Kerogens as Analogues for Organic Macromolecular Materials in Aqueously Altered Carbonaceous Chondrites

Abstract Understanding the processes involved in the evolution of organic matter in the early Solar System requires extensive experimental work. The scientifically valuable carbonaceous chondrites are principal targets for organic analyses, but these meteorites are rare. Meteoritic analog materials available in larger quantities, on which experiments can be performed, would be highly beneficial. The bulk of the organic inventory of carbonaceous chondrites is made up of solvent-insoluble macromolecular material. This high-molecular-weight entity provides a record of thermal and aqueous parent-body alteration of precursor organic structures present at the birth of the Solar System. To identify an effective analogue for this macromolecular material, we analyzed a series of terrestrial kerogens by pyrolysis–gas chromatography–mass spectrometry. Type I and II kerogens are unsuitable analogues owing to their highly aliphatic nature. Type III kerogens show some similarities to meteoritic macromolecular materials...