Introduction to Science

Geologic Time ScaleMr. SkirbstEarth ScienceTopic 251Geologic Time Scale2Geologic Time ScaleDescribing and dividing major events of Earths history3Geologic Time ScaleEra - longest divisionof geologic time

4Geologic Time ScaleEra - longest divisionof geologic time4 Major Eras

5Geologic Time ScaleEra - longest divisionof geologic time4 Major ErasPeriod sub-divisionsof eras

6Geologic Time ScalePrecambrian - early Earth 7Geologic Time ScalePrecambrianPaleozoic old life8Geologic Time ScalePrecambrianPaleozoicMesozoic middle life9Geologic Time ScalePrecambrianPaleozoicMesozoicCenozoic current life

10Precambrian Era4.6 bya 570 mya

11Precambrian Era4.6 bya 570 myaEarth formed12Precambrian Era4.6 bya 570 myaEarth formedSeas and mountains formed13Precambrian Era4.6 bya 570 myaEarth formedSeas and mountains formedSimple life-forms in sea

14Precambrian Era4.6 bya 570 myaEarth formedSeas and mountains formedSimple life-forms in seaOxygen builds up in air

15Paleozoic Era570 mya 225 mya

16Paleozoic Era570 mya 225 myaDivided into 6 periodsbased on major events

17Paleozoic EraCambrian sea-dwelling inverts.18Paleozoic EraCambrian sea-dwelling inverts.Ordovician first fish appear

19Paleozoic EraCambrian sea-dwelling inverts.Ordovician first fish appearSilurian first land plants

20Paleozoic EraCambrian sea-dwelling inverts.Ordovician first fish appearSilurian first land plantsDevonian first amphib. + forests

21Paleozoic EraCambrian sea-dwelling inverts.Ordovician first fish appearSilurian first land plantsDevonian first amphib. + forestsCarboniferous swamps, ferns, insects, reptiles22Paleozoic EraCambrian sea-dwelling inverts.Ordovician first fish appearSilurian first land plantsDevonian first amphib. + forestsCarboniferous swamps, ferns etcPermian conifers, lots of reptiles23Paleozoic EraMemory aid: COSDCP

DC24Paleozoic EraMemory aid: COSDCP

Come Over, Said DC Pig

DC25Mesozoic Era225 mya 65 mya

26Mesozoic Era225 mya 65 myaTriassic 1st dinosaurs + mammals

27Mesozoic Era225 mya 65 myaTriassic 1st dinosaurs + mammalsJurassic 1st birds + big dinos

28Mesozoic Era225 mya 65 myaTriassic 1st dinosaurs + mammalsJurassic 1st birds + big dinosCretaceous 1st flowers + dinos die out

29Cenozoic Era65 mya PresentTertiary mammals, present-day features

30Cenozoic Era65 mya PresentTertiary mammals, present-day featuresQuaternary humans, ice ages

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