c89a5c28_mical_Sediments_and_Landscapes__1
[0] Paucity of microfossils [2] Several studies are notable for presence of microfossils, while others are notable for analysis of organic residues only. [3] This model explains the paucity of microfossils, because Mn-encrusted cell walls are redistributed at the nanometer scale. [4] Model proponents hope to use microfossils to explore extraterrestrial life, but this makes little sense given poor preservation. [1] 
This model would predict the paucity of microfossils.
Rock Varnish Chapter 8 in Geochemical Sediments and Landscapes
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