Chapter 6.3 Gunflint Stromatolites: Microfossil Distribution in Relation to Stromatolite Morphology

Abstract

Publisher Summary This chapter discusses the microfossil distribution in relation to Stromatolite morphology. The gunflint stromatolites and living pertinent examples provide data for a biological-environmental approach to interpretation of stromatolite morphology. The stromatolites of the Gunflint Iron Formation, with their well-preserved microflora, are the source of valuable information for determining the possible relationships between microorganisms, the physical environment, and stromatolite morphology. In the Gunflint, it appears that minor changes in the physical environment caused changes in the microbial assemblage and stromatolite morphology. Viewing the distribution of stromatolites in time and space during the Proterozoic, this chapter considers that the evolution of new members or the extinction of existing members in cyanophytic and bacterial mat-building communities among taxa possibly as low as the specific and generic level, in interaction with the environment, may be responsible for the increase in diversity and the time-restriction of these stromatolite morphologies.