A network of ten regional cross sections across New York reveals the detailed subsurface stratigraphy of the Medina Group (Lower Silurian), Clinton Group (Lower to Upper Silurian), and Lockport Group (Upper Silurian). Both gamma-ray logs and sample logs were used to correlate from outcrop to subcrop and well to well throughout the subsurface of New York. Approximately 250 well logs and 125 sample logs were incorporated into this study.

The study indicates that the Medina Group can be subdivided into the Whirlpool, Power Glen, and Grimsby Formations. The Clinton Group is subdivided into 16 formations. In the west, the Clinton Group includes the Thorold, Reynales, Irondequoit, and Rochester Formations. In central and eastern New York, this group is subdivided into the Oneida, Bear Creek, Kodak, Sodus, Wolcott, Otsquaqo, Willowvale, Sauquoit, Williamson, Irondequoit, Dawes, and Heidimer Formations. Two formations are recognized in the Lockport Group: the Sconondoa and Ilion Formations.

In addition to the stratigraphy, the cross sections also display the

End_Page 1921------------------------------

regional geometry of this rock sequence, vertical and lateral changes in lithology, and the presence and nature of several unconformities.

End_of_Article - Last_Page 1922------------