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Notes on video lecture:
Measuring Geologic Time
Choose from these words to fill the blanks below:
multicellular, jawed, complex, oceans, oceans, geological, flourish, Paleocene, Pliocene, Ediacaran, Cretaceous, terrestrial, colder, Hadean, recovery, carbon, ended, lizards, invertebrates, Ice, civilizations, lagerstätte, dinosaurs, billions, archaic, flowering, amniotes, formation, Carboniferous, ecosystems, estimates, transition, Phanerozoic, Cambrian, Silurian, humid, glaciations, diversification, arthropods, rainforests, birds, Moon, Earth, cooled, oxygen, glaciations, avian, Miocene, crust, two, recover, demise, reptiles, fossils, land, single, dominant, land, Mesozoic, dubbed, extinction, Coupure, Holocene, ocean, vascular, annum, chimpanzees, bony, Devonian, better, rudists, forests
history of the           
events in                  of years ago
4.57 Earth's                    (Hadean Eon)
3.8 first evidence of              (Archaen Eon)
2.5 oxygen-rich atmosphere (Proterozoic Eon)
0.542 explosion of                (Phanerozoic Eon)
0.065 dinosaurs go extinct (                       Eon - Cenozoic Era)
0.0002 first hominids
0.000022 maximum extent of last        Age
classification scheme for                      time, from largest to smallest
speak in these terms since these dates are rough                    based on various ways of determining how long ego events occurred
eons
eras
periods or systems
epochs or series
stages
abbreviations
Ma (mega           )
million years
Ga (giga annum)
billion years
four eons
PRECAMBRIAN supereon:
[1]              Eon - 4570 Ma
named after Hades, or the under world
formation of Earth and         
molten earth surface
formation of earliest           
[2] Archaen Eon - 3800 Ma
[ar-KEE-an]
             formed
            -celled animals
geologic record documents these single-celled fossils their structures they left behind called surmatelites
process of plate tectonics was just beginning
low              concentration in air
[3] Proterozoic Eon - 2500 Ma
increasing oxygen concentration in the atmosphere
periods of                        including a period in which the Earth may have been entirely covered in ice
                           life began evolving
                   Period (635-542 Ma)
first multicellular life
first appearance worldwide of somewhat complicated trace fossils
[4] Phanerozoic Eon - 542 Ma
increasing complexity of multicellular life
the colonization of life from the ocean onto the          of plants and animals
the eon in which                life began to flourish
but also with periodic extinction events that almost            life on earth
1. Paleozoic Era (542,000,000 - 251,000,000)
                 Period - 542 Ma
rapid                                of lifeforms known as the Cambrian explosion
produced first representatives of all modern animal phyla
high proportion of                                  sedimentary deposits with exceptional preservation
where "soft" parts of organisms are preserved as well as their more resistant shells
therefore we understand Cambrian biology              than some later periods
Ordovician Period - 485 Ma
life continued to                 
end of period marked by a significant mass extinction
                          , namely molluscs and arthropods, dominated oceans
fish, the world's first true vertebrates, continued to evolve, first            fish
         life had yet to diversify
                 Period - 444 Ma
diversification of jawed and          fish
life also began to appear on land in the form of small, moss-like,                  plants which grew beside lakes, streams, and coastlines
small terrestrial                      (insects, spiders)
but terrestrial life would not greatly diversify and affect the landscape until the                 
Devonian Period - 419 Ma
free-sporing vascular plants began to spread across dry land, forming extensive                which covered the continents
fish reached substantial diversity during this time, leading the Devonian to often be              the "Age of Fish"
Carboniferous Period - 358 Ma
                       life was well established
amphibians were the                  land vertebrates
one branch would eventually evolve into                 
Permian Period - 298 Ma
the diversification of the early                  into the ancestral groups of the mammals, turtles, lepidosaurs and archosaurs
2.                  Era - 250 Ma
Triassic Period - 250 Ma
began in the wake of the Permian–Triassic                      event, which left the Earth's biosphere impoverished
it took into the middle of the period for life to                its former diversity
the first true mammals
Jurassic Period - 200 Ma
land dominated by                   
supercontinent Pangaea had begun rifting into        landmasses
created more coastlines and shifted the continental climate from dry to           
many of the arid deserts of the Triassic were replaced by lush                       
first            and earliest               
Cretaceous Period - 145 Ma
oceans and seas were populated with now-extinct marine reptiles, ammonites and               
dinosaurs continued to dominate on land
new groups of mammals and birds, as well as                    plants, appeared
ended with a large mass extinction, the Cretaceous–Paleogene extinction event, in which many groups, including non-           dinosaurs, pterosaurs and large marine reptiles, died out
3. Cenozoic Era (65,000,000 - today)
Paleogene Period - 65 Ma
Paleocene Epoch - 65 Ma
brackets two major events in Earth's history: (1) the              of non-avian dinosaurs, giant marine reptiles and much other fauna and flora, and (2) the Paleocene–Eocene Thermal Maximum, a geologically brief interval characterized by extreme changes in climate and              cycling
Eocene - 56 Ma
includes the warmest climate in the Cenozoic Era when little or no ice was present on the planet, but ends in an much              climate
ended in a major extinction event called the Grande                (the "Great Break" in continuity) or the Eocene–Oligocene extinction event
Oligocene - 33 Ma
an important time of                     , a link between the                world of the tropical Eocene and the more modern ecosystems of the Miocene
Neogene Period - 23 Ma
Miocene - 23 Ma
             in a series of ice ages
apes arose and diversified becoming widespread in the Old World
ancestors of humans split away from the ancestors of the                       
Pliocene - 5.3 Ma
cooled down from the                temperatures
Quaternary Period - 2.5 Ma
Pleistocene - 2.5 Ma
recent period of repeated glaciations
                 (11,700 - 1800)
current warm period
(proposed) Anthropocene (1800 - present)
epoch in which humans are affecting the climate
mnemonic for eons and eras of geological time containing life forms on Earth
Proterozoic Eon
(E)VERY - Ediacran Period - 635 Ma - single-celled organisms
Phanerozoic Eon
Paleozoic Era - (FISH) - 542 Ma
(C)AMEL - Cambrian Period - 542 Ma - multicelled diversity explosion
(O)FTEN - Ordovician Period - 485 Ma - diversified            life
(S)ITS - Silurian Period - 444 Ma - early jawed and boned fish
(D)OWN - Devonian Period - 419 Ma - the age of fish
(C)AREFULLY -                            Period - 358 Ma - dominant amphibians
(P)ERHAPS - Permian Period - 298 Ma - mammal ancestral groups
Mesozoic Era - (DINOSAURS) - 250 Ma
(T)HEIR - Triassic Period - 250 Ma - extinction and                 , therapsids and first mammals
(J)OINTS - Jurassic Period - 200 Ma - age of reptiles, first birds
(C)REAK -                      Period - 145 Ma - new mammals, ended with dinosaur extinction
Cenozoic Era - (MAMMALS) - 65 Ma
Paleogene Period - 65 Ma
(P)ERHAPS -                    Epoch - 65 Ma - dinosaurs gone, changes in climate
(E)FFECTIVE - Eocene Epoch - 56 Ma - warmest, no ice on planet
(O)ILING - Oligocene Epoch - 33 Ma - transition from tropical to modern                     
Neogene Period - 23 Ma
(M)IGHT - Miocene Epoch - 23 Ma - humans and chimpanzees split
(P)ROLONG -                  Epoch - 5 Ma - climate cooled
Quaternary Period
(P)ERFECT - Pleistocene Epoch - 2 Ma - repeated                       , humans evolved into present form
(H)EALTH - Holocene (11,700 - ca. 1800) - current warm period, major human                           
(A)GAIN - (proposed) Anthropocene (ca. 1880) - humans altering the climate

Vocabulary:

stromatolites, n. [stroh-MAH-toh-lights] from the Greek στρώμα (mattress) and λίθος (rock), layered bio-chemical accretionary structures formed in shallow water by the trapping, binding and cementation of sedimentary grains by biofilms, or multi-layered sheet of microorganisms, especially cyanobacteria, a phylum (or division) of bacteria that obtain their energy through photosynthesis  "By producing gaseous oxygen as a byproduct of photosynthesis, cyanobacteria are thought to have converted the early reducing atmosphere into an oxidizing one, causing "rusting of the Earth" and dramatically changing the composition of life forms on Earth by stimulating biodiversity and leading to the near-extinction of oxygen-intolerant organisms, and thus stromatolites provide ancient records of life on Earth through fossil remains which might date from more than 3.5 billion years ago."

Spelling Corrections:

sedamentarysedimentary

Ideas and Concepts:

From the know-your-eons department, via this evening's Our Earth's Climate, History, and Processes class: "The history of the Earth is divided into four eons:(1) THE HADEAN EON (4,570,000,000-3,800,000,000 years ago) from the Greek Ἅιδης, or underworld, during most of which the Earth had a molten surface, endured heavy bombardments including what eventually became its Moon, and ended in the formation of the earliest crust layers. (2) ARCHAEN EON (3,800,000,000-2,500,000,000 years ago) from the Greek Αρχή, meaning "ancient", during which time the oceans formed, the process of plate tectonics was just beginning, single-celled animals began to evolve, and very low concentrations of oxygen were in air, (3) PROTEROZOIC EON (2,500,000,000-542,000,000 years ago) from the Greek πρότερος ("former") and ζωή ("life"), included increasing oxygen concentration in the atmosphere, periods of glaciations including a period in which the Earth may have been entirely covered in ice, and multicellular life began evolving, (4) PHANEROZOIC EON (542,000,000 years ago to today) from the Greek φανερός ("visible") and ζωή ("life"), included increasing complexity of multicellular life, the colonization of plants and animals from the ocean onto the land where complex life began to flourish, but not without periodic extinction events that almost ended life on Earth."
Mnemonic device for remembering the periods of the Phanerozoic Era, via this evening's Earth's Climate, History, and Processes class: "(E)very (C)amel (O)ften (S)its (D)own (C)arefully, (P)erhaps (T)heir (J)oints (C)reak --> (E)diacara, (C)ambrian, (O)rdovician, (S)ilurian, (D)evonian, (C)arboniferous, (P)ermian, (T)riassic, (J)urassic, (C)retaceous."
From the know-your-Cenozoic-epochs department via this evening's Earth's Climate, History, and Processes class: "PALEOCENE EPOCH (65,000,000 - 56,000,000) brackets two major events in Earth's history:(1) the demise of non-avian dinosaurs, giant marine reptiles and much other fauna and flora, and (2) the Paleocene–Eocene Thermal Maximum, a geologically brief interval characterized by extreme changes in climate and carbon cycling. EOCENE EPOCH (56,000,000 - 33,000,000) includes the warmest climate in the Cenozoic Era when little or no ice was present on the planet, but ends in an much colder climate, ended in a major extinction event called the Grande Coupure (the "Great Break" in continuity) or the Eocene–Oligocene extinction event. OLIGOCENE EPOCH (33,000,000 - 23,000,000), an important time of transition, a link between the archaic world of the tropical Eocene and the more modern ecosystems of the Miocene. MIOCENE EPOCH (23,000,000 - 5,333,000) cooled in a series of ice ages, apes arose and diversified becoming widespread in the Old World, ancestors of humans split away from the ancestors of the chimpanzees. PLIOCENE EPOCH (5,333,000 - 2,588,000) cooled down from the Miocene temperatures. PLEISTOCENE EPOCH (2,588,000 - 11,700) recent period of repeated glaciations. HOLOCENE EPOCH (11,700 - present) current warm period."
Measuring Geologic Time
Rocks and Minerals