Sulfur isotopes of iron sulfides in Devonian- Mississippian shales of the Appalachian Basin: control by rate of sedimentation.

Abstract

In modern sediments, the isotopic composition of S in iron sulfides appears to be controlled by sedimentation rate and by degree of contact of the basin with open seawater. A relationship is derived between del34S and sedimentation rate, which is then applied to data from ancient rocks. In the shales of the Appalachian Basin there is a clear-cut correspondence between S isotopes and inferred relative rates of sedimentation. Using the equation from recent sediments gives reasonable values for the relative rates of deposition of the various sedimentary units, but the absolute values seem too high by a factor of about 5.-from Author