Ratios of biogenic elements for distinguishing recent from fossil microorganisms

摘要

The ability to distinguish possible microfossils from recent biological contaminants is of great importance to Astrobiology In this paper we discuss the application of the ratios of life critical biogenic elements (C/O; C/N; and C/S) as determined by Energy Dispersive X-ray Spectroscopy (EDS) to this problem. Biogenic element ratios are provided for a wide variety of living cyanobacteria and other microbial extremophiles, preserved herbarium materials, and ancient biota from the Antarctic Ice Cores and Siberian and Alaskan Permafrost for comparison with macrofossils and microfossils in ancient terrestrial rocks and carbonaceous meteorites.