Depositional Environment of the Brassfield Dolomite

The Brassfield Dolomite (Lower Silurian) was most likely deposited in warm, shallow, mildly agitated seas.  These environments probably existed across a transgressing shallow platform shelf.  The Brassfield Dolomite represents the near-shore environment at the onset of a regional transgression.  Upper Silurian rocks above the Brassfield represent a further progression into deeper environments as the Silurian seas approached their maximum depths.  

For a picture of the geographical location of the North American continent during the Early Silurian, visit http://vishnu.glg.nau.edu/rcb/430NAt.jpg

The Brassfield Dolomite is the oldest formation of the Silurian age rocks present in Kentucky.  Below is a column of the revised nomenclature for the Silurian System in Kentucky.