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Notes on video lecture:
Measuring Geologic Time
Notes taken by Edward Tanguay on June 19, 2015 (go to class or lectures)
Choose from these words to fill the blanks below:
archaic, birds, carbon, dinosaurs, lagerstätte, glaciations, humid, extinction, cooled, ecosystems, Paleocene, vascular, ended, bony, Coupure, multicellular, estimates, Carboniferous, flourish, Silurian, complex, Pliocene, oxygen, Devonian, transition, Ediacaran, land, forests, Ice, Earth, civilizations, land, two, arthropods, Miocene, glaciations, chimpanzees, demise, diversification, rainforests, flowering, invertebrates, lizards, geological, formation, Hadean, colder, Holocene, reptiles, Moon, single, fossils, recovery, annum, Cambrian, dubbed, rudists, Mesozoic, ocean, jawed, recover, avian, dominant, billions, oceans, Cretaceous, Phanerozoic, amniotes, better, crust, terrestrial, oceans
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history of the           
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events in                  of years ago
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4.57 Earth's                    (Hadean Eon)
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3.8 first evidence of              (Archaen Eon)
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2.5 oxygen-rich atmosphere (Proterozoic Eon)
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0.542 explosion of                (Phanerozoic Eon)
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0.065 dinosaurs go extinct (                       Eon - Cenozoic Era)
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0.0002 first hominids
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0.000022 maximum extent of last        Age
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classification scheme for                      time, from largest to smallest
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speak in these terms since these dates are rough                    based on various ways of determining how long ego events occurred
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eons
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eras
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periods or systems
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epochs or series
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stages
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abbreviations
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Ma (mega           )
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million years
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Ga (giga annum)
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billion years
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four eons
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PRECAMBRIAN supereon:
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[1]              Eon - 4570 Ma
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named after Hades, or the under world
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formation of Earth and         
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molten earth surface
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formation of earliest           
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[2] Archaen Eon - 3800 Ma
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[ar-KEE-an]
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             formed
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            -celled animals
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geologic record documents these single-celled fossils their structures they left behind called surmatelites
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process of plate tectonics was just beginning
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low              concentration in air
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[3] Proterozoic Eon - 2500 Ma
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increasing oxygen concentration in the atmosphere
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periods of                        including a period in which the Earth may have been entirely covered in ice
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                           life began evolving
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                   Period (635-542 Ma)
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first multicellular life
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first appearance worldwide of somewhat complicated trace fossils
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[4] Phanerozoic Eon - 542 Ma
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increasing complexity of multicellular life
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the colonization of life from the ocean onto the          of plants and animals
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the eon in which                life began to flourish
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but also with periodic extinction events that almost            life on earth
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1. Paleozoic Era (542,000,000 - 251,000,000)
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                 Period - 542 Ma
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rapid                                of lifeforms known as the Cambrian explosion
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produced first representatives of all modern animal phyla
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high proportion of                                  sedimentary deposits with exceptional preservation
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where "soft" parts of organisms are preserved as well as their more resistant shells
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therefore we understand Cambrian biology              than some later periods
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Ordovician Period - 485 Ma
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life continued to                 
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end of period marked by a significant mass extinction
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                          , namely molluscs and arthropods, dominated oceans
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fish, the world's first true vertebrates, continued to evolve, first            fish
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         life had yet to diversify
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                 Period - 444 Ma
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diversification of jawed and          fish
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life also began to appear on land in the form of small, moss-like,                  plants which grew beside lakes, streams, and coastlines
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small terrestrial                      (insects, spiders)
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but terrestrial life would not greatly diversify and affect the landscape until the                 
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Devonian Period - 419 Ma
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free-sporing vascular plants began to spread across dry land, forming extensive                which covered the continents
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fish reached substantial diversity during this time, leading the Devonian to often be              the "Age of Fish"
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Carboniferous Period - 358 Ma
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                       life was well established
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amphibians were the                  land vertebrates
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one branch would eventually evolve into                 
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Permian Period - 298 Ma
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the diversification of the early                  into the ancestral groups of the mammals, turtles, lepidosaurs and archosaurs
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2.                  Era - 250 Ma
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Triassic Period - 250 Ma
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began in the wake of the Permian–Triassic                      event, which left the Earth's biosphere impoverished
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it took into the middle of the period for life to                its former diversity
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the first true mammals
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Jurassic Period - 200 Ma
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land dominated by                   
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supercontinent Pangaea had begun rifting into        landmasses
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created more coastlines and shifted the continental climate from dry to           
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many of the arid deserts of the Triassic were replaced by lush                       
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first            and earliest               
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Cretaceous Period - 145 Ma
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oceans and seas were populated with now-extinct marine reptiles, ammonites and               
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dinosaurs continued to dominate on land
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new groups of mammals and birds, as well as                    plants, appeared
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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
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3. Cenozoic Era (65,000,000 - today)
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Paleogene Period - 65 Ma
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Paleocene Epoch - 65 Ma
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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
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Eocene - 56 Ma
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includes the warmest climate in the Cenozoic Era when little or no ice was present on the planet, but ends in an much              climate
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ended in a major extinction event called the Grande                (the "Great Break" in continuity) or the Eocene–Oligocene extinction event
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Oligocene - 33 Ma
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an important time of                     , a link between the                world of the tropical Eocene and the more modern ecosystems of the Miocene
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Neogene Period - 23 Ma
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Miocene - 23 Ma
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             in a series of ice ages
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apes arose and diversified becoming widespread in the Old World
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ancestors of humans split away from the ancestors of the                       
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Pliocene - 5.3 Ma
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cooled down from the                temperatures
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Quaternary Period - 2.5 Ma
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Pleistocene - 2.5 Ma
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recent period of repeated glaciations
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                 (11,700 - 1800)
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current warm period
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(proposed) Anthropocene (1800 - present)
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epoch in which humans are affecting the climate
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mnemonic for eons and eras of geological time containing life forms on Earth
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Proterozoic Eon
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(E)VERY - Ediacran Period - 635 Ma - single-celled organisms
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Phanerozoic Eon
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Paleozoic Era - (FISH) - 542 Ma
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(C)AMEL - Cambrian Period - 542 Ma - multicelled diversity explosion
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(O)FTEN - Ordovician Period - 485 Ma - diversified            life
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(S)ITS - Silurian Period - 444 Ma - early jawed and boned fish
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(D)OWN - Devonian Period - 419 Ma - the age of fish
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(C)AREFULLY -                            Period - 358 Ma - dominant amphibians
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(P)ERHAPS - Permian Period - 298 Ma - mammal ancestral groups
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Mesozoic Era - (DINOSAURS) - 250 Ma
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(T)HEIR - Triassic Period - 250 Ma - extinction and                 , therapsids and first mammals
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(J)OINTS - Jurassic Period - 200 Ma - age of reptiles, first birds
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(C)REAK -                      Period - 145 Ma - new mammals, ended with dinosaur extinction
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Cenozoic Era - (MAMMALS) - 65 Ma
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Paleogene Period - 65 Ma
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(P)ERHAPS -                    Epoch - 65 Ma - dinosaurs gone, changes in climate
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(E)FFECTIVE - Eocene Epoch - 56 Ma - warmest, no ice on planet
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(O)ILING - Oligocene Epoch - 33 Ma - transition from tropical to modern                     
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Neogene Period - 23 Ma
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(M)IGHT - Miocene Epoch - 23 Ma - humans and chimpanzees split
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(P)ROLONG -                  Epoch - 5 Ma - climate cooled
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Quaternary Period
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(P)ERFECT - Pleistocene Epoch - 2 Ma - repeated                       , humans evolved into present form
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(H)EALTH - Holocene (11,700 - ca. 1800) - current warm period, major human                           
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(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:

sedamentary ⇒ sedimentary

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