In southern Indiana and northwestern Kentucky, 18 paracontinuous disconformities separate 17 sedimentary packages within the Middle-Upper Devonian, while paracontinuity 19 marks the Upper Devonian-Lower Mississippian boundary and paracontinuity 20 marks the Kinderhookian-Osagean boundary. At the base of the Devonian sequence, the contact is a paraconformable disconformity between the Middle Silurian Louisville Limestone and the Early? (Emsian)-middle (Eifelian) Devonian Jeffersonville Limestone, with an estimated time gap of 25-30 million years along the unconformity.
Nineteen fish bone beds are associated with and immediately overlie paracontinuities 2-20, while the first paracontinuity (between the underlying Amphipora ramosa Zone and the overlying Brevispirifer gregarius Zone of the Jeffersonville Limestone) is not associated with a bonebed.
The 17 sedimentary packages are of various stratigraphic taxa, as members, formations, groups, and series and are discriminated not only by the widespread disconformities at their bases, but also by fossil zones. Further, these sedimentary packages are enclosed in a framework bracketed by distinct and separately recognizable metabentonites: the Kawkawlin, Onondaga Indian Nation, and Tioga in the Middle Devonian, and the Belpre, Center Hill, and Howardstown in the Upper Devonian. There are at least 33 less important metabentonites, but some of marker significance, as the Lake Chelan Metabentonite, associated with bone bed 4 at the base of the Upper Paraspirifer acuminatus -Spirifer duodenarius Zone of the Jeffersonville.
AAPG Search and Discovery Article #90926©1999 AAPG Eastern Section Meeting, Indianapolis, Indiana