Wikimedi'Òc

Catskill section.jpg - Urban~commonswiki

Geologic cross section of Devonian strata from New York to Alabama.svg - File Upload Bot (Magnus Manske)

Kittatinny Mountain Cross Section.jpg - Awickert

Cross-section of the Helderberg Ridge, NY.png - Geo Swan

Helderberg Group.png - Jpr2014

USGS 2006 1237 Fig7b.png - Mikenorton

Annual report of the Regents - New York State Museum. (1895) (19180365389).jpg - Fæ

Annual report of the Regents - New York State Museum. (1896) (19179983869).jpg - Fæ

Bulletin - New York State Museum (1897) (20441767255).jpg - Fæ

NPS delaware-water-gap-geologic-map.jpg - RKBot

Catskill section.gif - Hike395