Eolian Dust and the Origin of Sedimentary Chert

C. Blaine Cecil

doi:10.3133/ofr20041098

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Eolian Dust and the Origin of Sedimentary Chert

C. Blaine Cecil

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Abstract

This paper proposes an alternative model for the primary source of silica contained in bedded sedimentary chert. The proposed model is derived from three principal observations as follows: (1) eolian processes in warm-arid climates produce copious amounts of highly reactive fine-grained quartz particles (dust), (2) eolian processes in warm-arid climates export enormous quantities of quartzose dust to marine environments, and (3) bedded sedimentary cherts generally occur in marine strata that were deposited in warm-arid paleoclimates where dust was a potential source of silica. An empirical integration of these observations suggests that eolian dust best explains both the primary and predominant source of silica for most bedded sedimentary cherts.

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C. Blaine Cecil. 2004. Eolian Dust and the Origin of Sedimentary Chert. https://doi.org/10.3133/ofr20041098

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