The Story of the Earth in 33 Minutes From Potholer54 0 Randall Gross ScienceSeptember 2019Sunday, September 29, 2019 at 4:32 am PDT • Views: 1,887 Global Warming Global Cooling Geological Evidence Periods Cambrian Jurassic Ordovician Tertiary Quaternary Potholer54 Oceans Mountains Interglacial