It was discovered yesterday by staff that EPA updated the Ecoregion delineations for Tennessee. According to EPA, they did the work back in 2001 and again in 2003 but failed to notify anyone at TDEC of the changes. Thanks to Courtney Brame for noticing the changes.
Anyway, it appears we now have 6 new ecoregion delineations.
73b Northern Pleistocene Valley Trains --- split out of a portion of 73a Mississippi Alluvial Plains
69c Cumberland Mountain Thrust Block --- split out of 69d Dissected Appalachian Plateau; also changed this name in the old data 69d was called Cumberland Mountains
66j Broad Basins --- split out of 66g Southern Metasedimentary Mountains; This new area is in the Copper Basin area of the state
66i High Mountains --- split out of 66g Southern Metasedimentary Mountains; These new areas are along the NC border
66k Amphibolite Mountains --- Split from 66d Southern Crystaline Ridges and Mountains; This new area is very small and located on the NC border in Johnson County, TN
68d Southern Table Plateaus --- In the old data set this was a very small blob on the southern border of TN and Alabama/Georgia that was considered 68a Cumberland Plateau
Also, it appears that they re delineated 71h Outer Nashville Basin so that it now connects with KY.
The image shows the new delineations highlighted in red.