geologic ages
40 subentries
- geologic ages (59:0.1-6)
- 1. Archeozoic (prelife era)
- 1 billion to 550 million years ago (59:0.2) (78:7.4)
- 2. Proterozoic (life-dawn era)
- 550 to 400 million years ago (58:7.1) (59:0.3)
- 3. Paleozoic (marine-life era)
- 400 to 150 million years ago (59:0.4) (59:6.11)
- Cambrian (trilobite age)
- 400 to 350 million years ago (59:1sec)
- Ordovician (invertebrate-animal age)
- 350 to 300 million years ago (59:2sec)
- Silurian (coral and brachiopod age)
- 300 to 275 million years ago (59:3sec)
- Devonian (age of plant life, fishes)
- 270 to 220 million years ago (59:4sec)
- Carboniferous (age of fern forests, frogs)
- 220 to 180 million years ago (59:5sec)
- Permian (seed-plant age; biologic tribulation)
- 170 to 150 million years ago (59:6sec)
- 4. Mesozoic (early land-life era)
- 150 to 50 million years ago (59:0.5) (60:4.6)
- Triassic (early-reptilian age)
- 150 to 125 million years ago (60:1sec)
- Jurassic (later-reptilian age)
- 125 to 100 million years ago (60:2sec)
- Cretaceous (age of flowering plants, birds)
- 100 to 50 million years ago (60:3-4secs)
- 5. Cenozoic (mammalian era)
- 50 million years ago to the present (61:0sec)
- Eocene (early-mammal age)
- 50 to 35 million years ago (61:1sec)
- Oligocene (advanced mammal age)
- 35 to 25 million years ago (61:2sec)
- Miocene (age of elephant and horse)
- 25 to 10 million years ago (61:3.15)
- Pliocene (mammalian migration stage)
- 10 to 1 million years ago (61:4sec)
- Pleistocene (ice age)
- 2 million to 100,000 years ago (61:5-7secs)
- Holocene (postglacial period)
- 35,000 years ago to the present (61:7.18)
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