PERIOD
Quaternary
∗ Ma
Cenozoic
2.7
17.7
Tertiary
10.9
21.9
9.7
∗ Ma
65.5
Mesozoic
80 Cretaceous
145.5
56 Jurassic
201.6
49 Triassic
251
EPOCH Red it’s in BBNP Not red where?
2.6 Holocene, Pleistocene Current ice age
Pliocene
Neogene: Human ancestors,
5.3
deer, dogs, bears, camels, sloths,
Miocene
cats, mastodons, asters, pinks
23
Oligocene Paleogene: Primates, grasses,
33.9
roses, cashews, grapes, unguEocene
lates, bats, rodents, marsupials,
55.8
Paleocene cetaceans, cacti, palms
65.5
(Extinction event) Flowering plants, broad-leaf
trees, figs, magnolias, bees, mammals, dinosaurs,
butterflies, moths, crocodiles
First flowering plants, ginkgoes, birds, sauropods,
theropods, pterosaurs, icthyosaurs, plesiosaurs, ancestral Sierra Nevada, Peninsular Ranges
(Extinction event) First dinosaurs, cycads, conifers,
modern corals, first mammals, frogs, lizards, ancestral Andes, Pangea supercontinent
(Extinction event) Dragonflies, beetles, cockroaches, cynodonts (mammal ancestors), conifers
Karoo ice age (south pole, Gondwana)
299
Gymnosperms, moss forests, ferns, spiders, sharks,
60 Carboniferous
amniote egg, reptiles, ancestral Rockies
359
(Extinction event) Giant fungi, ferns, horsetails,
forests, first sharks, bony fish, land arthropods, am57 Devonian
phibians, progymnosperms, ancestral Appalachians
416
Vascular plants at water’s edge, nematodes, cen28 Silurian
tipedes, corals, arthropods, fungi, first jawed fish
444
Hirnantian ice age, end Ordovician
(Extinction event) Cephalopods, giant nautiloids,
44 Ordovician
crinoids, bryozoa, coral reefs, first fish, Gondwana
488
Trilobites, small shelled fauna, echinoderms, fungi,
54 Cambrian
algae, perhaps lichen on land - no plants
542 Ma
Phanerozoic EON (New to geology? Try UC Museum of Paleontology)
Big Bend National Park—Missing Geology
Red text signifies BBNP formations present. GSA Geologic Time Scale.
Ga = “Billion years ago”
Ma = “Million years ago”
http://www.nps.gov/bibe/naturescience/geology.htm
Phanerozoic (visible life) is shown overleaf
EON
ERA
Proterozoic
ERA
Neoproterozoic 1 Ga–.542
Ediacaran biota 630 Ma–542 Ma
Cryogenian glaciations (snowball?)
Breakup of Rodinia
Mesoproterozoic 1.6–1
Rodinia supercontinent
Sexual reproduction
O2 – today’s level and beyond
Paleoproterozoic 2.5–1.6
Start of eukaryotic life (that’s us!)
Huronian glaciation (snowball?)
Banded iron formations
Build-up of O2
Neoarchean 2.8–2.5
Oxygenation of atmosphere begins
Cyanobacteria
CO2 plus H2 O photosynthesis
Mesoarchean 3.2–2.8
Pongola - oldest ice age?
Vaalbara – earth’s first supercontinent?
Prokaryotic microfossils - life for sure
Paleoarchean 3.6–3.2
High methane low oxygen atmosphere
Stromatolites - bacterial fossils?
Eoarchean 3.8–3.6
Formations in this era are rare
High 12 C to 13 C ratios in some
formations - life possible?
4.6–3.8 Ga
Late Heavy Bombardment (4.1-3.8 Ga)
Earliest rock formations known (4 Ga?)
Earliest zircons studied (4.4 Ga)
∗ Ma=“Million
years ago” Dates taken from 2009 Geologic Time Scale (overleaf)
For MISSING GEOLOGY notes: http://www.cse.ucsd.edu/~gill
Archean
Hadean
Paleozoic
48 Permian
START HERE: Earth - Moon System Formed 4.6 Ga