A Geological Hand Atlas of the Sixty-Seven Counties of Pennsylvania
Electronic version of an 1885 report. Includes descriptions and geologic maps for each county.
http://www.libraries.psu.edu/emsl/guides/X.html - Detail
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Pennsylvania Council of Professional Geologists
Serve the professional and commercial interests of member firms that provide or utilize geological services.
http://www.pcpg.org/ - Detail
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Pittsburgh Geological Society
Organization of professionals and amateurs. Includes meeting schedule, maps and publications on regional geology, geohazards, and other topics, issue statements, job postings, and other resources.
http://pittsburghgeologicalsociety.org/ - Detail
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