Before revision: Earth Science News, Maps, Dictionary, Articles, Jobs American Geophysical Union American Geosciences Institute European Geosciences Union European Federation of Geologists Geological Society of America Geological Society of London Video-interviews with famous geologists Geology OpenTextbook Chronostratigraphy benchmark
After revision: Earth Science News, Maps, Dictionary, Articles, Jobs American Geophysical Union American Geosciences Institute European Geosciences Union European Federation of Geologists Geological Society of America Geological Society of London Video-interviews with famous geologists Geology OpenTextbook Chronostratigraphy benchmarks The principles and objects of geology, with special reference to the geology of Egypt (1911) W. F. Hum