In the Salina Formation (Upper Silurian) the B unit can be divided into three subunits which are correlative from Michigan to the Appalachian basin. Underlying the area of Retsof, New York, the B-2 subunit contains five mappable salt beds that appear to correlate with similar beds in the Michigan basin. The B-3 subunit, or the "Retsof" bed, has the greatest continuity of any of the salt beds of the B unit. The D unit also has been separated into three subunits, although the lower subunit, D-1 salt, is absent in many areas of Ohio and Michigan. At Watkins Glen, New York, it was necessary to subdivide the F unit into three subunits in order to facilitate correlations where two fault systems are present.

Recently electric logging techniques have made the detection of faults possible by correlation of repeat sections of Salina carbonate rocks in the area of Watkins Glen, New York. Many of the complex structural salt features of that area are being resolved by the use of electric logs. Faulting in bedded salt is illustrated graphically by a pictorial review of the exposures created in salt beds during the driving of a sloping tunnel through the B-2 unit underlying the Retsof mine.

In some areas where bedded salt is present, the major anomalies are due to the solution of the salt beds by meteoric waters which resulted in the formation of slumps. In other areas, such as Retsof, New York, Cleveland, Ohio, and Watkins Glen, New York, faulting is the major structural disturbance. At Ludlowville, New York, geothermal heat and stresses associated with the formation of the Portland Point anticline have caused folding and flowage to form a metamorphosed salt.