Geologic units in Oswego county, New York

Undifferentiated Medina Group and Queenston Formation (Upper Ordovician - Lower Silurian) at surface, covers 35 % of this area

Grimsby Formation-sandstones, shale; and Queenston Formation-shale, siltstone.

Oswego Sandstone (Upper Ordovician) at surface, covers 32 % of this area

Oswego Sandstone

Clinton Group (Lower Silurian) at surface, covers 23 % of this area

Herkimer Sandstone; Kirkland Hematite; Willowvale Shale; Westmoreland Hematite; Sauquoit Formation-sandstone, shale; Oneida Conglomerate.

Pulaski and Whetstone Gulf Formations (Upper Ordovician) at surface, covers 10 % of this area

Siltstone, shale.

Undifferentiated Medina Group and Queenston Formation (Upper Ordovician - Lower Silurian) at surface, covers 1 % of this area

Grimsby Formation-sandstones, shale; and Queenston Formation-siltstone, shale.

Lockport Group (Upper Silurian) at surface, covers < 0.1 % of this area

Oak Orchard and Penfield Dolostones; both replaced eastwardly by Sconondoa Formation-limestone, dolostone.

Utica Shale (Middle Ordovician) at surface, covers < 0.1 % of this area

Utica Shale