Ìgbà Sílúríà

The Silurian is a geologic period and system that extends from the end of the Ordovician Period, about 443.7 ± 1.5 Mya (million years ago), to the beginning of the Devonian Period, about 416.0 ± 2.8 Mya (ICS, 2004,^[5] chart). As with other geologic periods, the rock beds that define the period's start and end are well identified, but the exact dates are uncertain by several million years. The base of the Silurian is set at a major extinction event when 60% of marine species were wiped out. See Ordovician-Silurian extinction events.

Ìgbà Sílúríà

Ìgbà Sílúríà 443.7–416 ẹgbẹgbẹ̀rún ọdun sẹ́yìn PreЄ Є O S D C P T J K Pg N
Mean atmospheric O2 content over period duration	ca. 14 Vol %[1] (70 % of modern level)
Mean atmospheric CO2 content over period duration	ca. 4500 ppm[2] (16 times pre-industrial level)
Mean surface temperature over period duration	ca. 17 °C[3] (3 °C above modern level)
Sea level (above present day)	Around 180m, with short-term negative excursions[4]