1. Geologic map of the south half of the Shamokin quadrangle, Northumberland and Columbia Counties, Pennsylvania [cartographic material] Yale Public content 1973. 2012-11-27T19:24:46Z. 2013-03-18T20:47:08Z. Arndt, Harold H. U.S. Geological Survey. English. Public. Pennsylvania, Northumberland County, and Columbia County.