GEOLEX database Geologic Unit: Hortonville Usage: Hortonville Formation of Trenton Group (VT) Hortonville Slate of Trenton Group (VT*) Age: Ordovician, Middle* Geologic Province: New England province* Areal Extent: VT* Type Locality: Type area: Exposed around Hortonville, Castleton quadrangle, Rutland Co., VT (Keith, 1932). Unit Name History: Named Hortonville slate (Keith, 1932). Revised (Fowler, 1950). Revised to Hortonville formation of Trenton group (Doll and other, 1961). Note: If you need more information, please contact Nancy Stamm (nstamm@usgs.gov). Asterisks (*) indicate usage by the U.S. Geological Survey. Other usages by state geological surveys. "No current usage" implies that a name has been abandoned or that it has fallen into disuse. Former usage and, if known, replacement name given in parentheses (). Slashes (/) indicate unit name usage violates the 1983 North American Stratigraphic Code. This violation may be explained within brackets ([ ]). U.S. Department of the Interior, U.S. Geological Survey, Reston, VA, USA URL http://ngmdb.usgs.gov/ngmdb/ngm_catalog.ora.html Database project personnel Last modified: 7-Jan-2007