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EARLY PALEOZOIC EVENTSORDOVICIAN PALEOGEOGRAPHY
Subduction initiated on west coast NAGreywackes and volcanics accumulate
EARLY PALEOZOIC EVENTSORDOVICIAN PALEOGEOGRAPHY
Other Tectonic EventsWilliston Basin
Evaporites
Red River Formation
EARLY PALEOZOIC EVENTSORDOVICIAN PALEOCLIMATE
From the Early to Middle Ordovician, the earth experienced a milder climate in which the weather was warm and the atmosphere contained a lot of moisture.
However, when Gondwana finally settled on the South Pole during the Late Ordovician, massive glaciers formed causing shallow seas to drain and sea levels to drop.
This likely caused the mass extinctions that characterize the end of the Ordovician, in which 60% of all marine invertebrate genera and 25% of all families went extinct.