Histo Geol - Ch 4 Flashcards
Subdivisions of precambrian
Hadean
Archean
Proterozoic
Eras of the phanerozoic
Paleozoic
Mesozoic
Cenozoic
Peroids of the paleozoic
Cambrian, Ordovician, Silruian, Devonian, Carboniferous (Missisipian, Pensylvanian), Permian
COSDCaP
Peroids of the Mesozoic
Triassic, Jurassic, Cretaceous
Dino Tender Juicy Hotdog
Peroids of the Cenozoic
Paleogene, Neogene, Quaternary
Paleogene Epochs
Paleocene, Eocene, Oligocene
Neogene Epochs
Miocene, Pliocene
Quaterary Epochs
Pleistocene, Holocene
Earliest fossil record
- Hadean
- Proterozoic
- Archean
- Cambrian
- Archean
“Earliest shelled animals
- Hadean
- Proterozoic
- Archean
- Cambrian”
- Proterozoic
First fish
- Cambrian
- Ordivician
- Devonian
- Missipian
Cambrian
First land plants
- Cambrian
- Ordivician
- Devonian
- Missipian
Ordovician
First Amphibians
- Cambrian
- Ordivician
- Devonian
- Missipian
Devonian
First reptiles
- Cambrian
- Ordivician
- Devonian
- Missipian
Missisipian
Abundant coal forming swamps
- Pennsylvanian
- Permian
- Triassic
- Mississippian
Pennsylvanian
Formation of Pangea; appalaichians
- Pennsylvanian
- Permian
- Triassic
- Jurrasic
Permian
First mamals and dinos
- Pennsylvanian
- Permian
- Triassic
- Jurrasic
triassic
First Birds; Sierra Nevada formation
- Pennsylvanian
- Permian
- Triassic
- Jurrasic
Jurassic
Extinction of Dinos
- Cretaceous
- Eocene
- Pliocene
- Pleistoscene
Cretaceous
Formation of himalayas and alps
- Cretaceous
- Eocene
- Pliocene
- Pleistoscene”
Eocene
Earliest humans
- Cretaceous
- Eocene
- Pliocene
- Pleistoscene”
Pliocene
the start of pleistoscene was __ MYA
- 2.6
- 5.3
- 23
- 34
- ## 2.6
- 5.3 : Pliocene
- 23 : Miocene
- 34 : Oligocene
the start of Eocene was __ MYA
- 0.01147
-Current
- 56
- 66
- ## 56
- 0.01147 : Holocene
-Current : also Holocene - 66 : Paleocene
An epoch of the paleogene where its a portmanteu of “old” and “Eocene”
Paleocene
(palaios = old)
An epoch of the paleogene where it means “Dawn of the New”
Eocene
(Eos= dawn; kainos = new)
An epoch of the neogene where it means “Less New” (or literally Few New)
Oligocene
(Oligo= few; kainos = new)
An epoch of the neogene where it means “continuation of the recent”
Pliocene
(Pleon= more; kainos = new)
An epoch of the Quaternary where it means “most recent”
Pleistocene
(Pleistos= more; kainos = new)
An epoch of the Quaternary where it means entirely new”
Holocene
(Holo= whole; kainos = new)
Start of the Triassic
-251
-200
-146
-299
- ## 251
- 200 : Jurassic
- 146 : Cretaceous
- 299 : Permian
“Start of the Missisipian
-318
-359
-416
-444
- ## 359
- 318 : Pensylvanian
- 416 : Devonian
- 444 : Silurian
“Start of the Cambrian
- 416
- 444
- 488
- 512
-416 : Devonian
-444 : Silurian
-488 : Ordovician
Extrapolated the age of earth from a ball’s cooling rate
- Georges Louis de Buffon
- John Joly
- James Hutton
- Charles Lyell
- Georges Louis de Buffon
Extrapolated the age of earth from amount of salt from the world’s streams
- Georges Louis de Buffon
- John Joly
- James Hutton
- Charles Lyell
- John Joly
A radioactive decay where an unstable parent nucleus emits 2 p and 2 n
Alpha decay
Z = -2
A = -4
A radioactive decay where an electron is emitted from a neutron
Beta decay
Z = +1
A = 0
A radioactive decay where a proton captures an electron and is converted to a neutron
Electron Capture
Z = -1
A = 0
Uranium 238 decays into
Lead 206
One of the few intances in which radiometric dates can be obtained on seds
presene of Glauconite
Daugther Isotope of U235
- Th 232
- Pb 207
- K 40
- St 87
- ## Pb 207
- Th 232 : Parent isotope of Pb 208
- K 40 : Parent Isotope of Ar 40
- Sr 87 : Daugther Isotope of Rb 87
Effective Dating range of U238 to Pb206
- 100k to 4.6 b
- 10 m to 4.6 b
- 100 to 50k
- ## 10 m to 4.6 b (also applies ot Rb-St)
- 100k to 4.6 b : K-Ar
- 100 to 50k : Carbon Dating
Minerals suitable for U-Pb
- Ziron & Uraninite
- Mus, Kfelds
- Glauconite, Hb
- ## Ziron & Uraninite
- Mus, Kfelds : Rb/Sr
- Glauconite, Hb : K/Ar
If the minerals that contain both uranium isotopes have remained closed systems, the ages obtained from each parent–daughter ratio should agree closely. If they do, they are said to be __________, thus reflecting the time of crystallization of the magma. If the ages do not closely agree, they are said to be ___________,
concordant:
discordant
Effects of metamorphism on radiometric dating
drives out daughter atoms from a mineral;
yields the time of metamorphism rather time of crstallization
Used as a cross check for C14 dating
- Sm/Nd
- K/Ar
- U/Th
- Ar/Ar
-U/Th
Fission track effective dating
40k to 1.5 mya
A thermal maximum starting 59 mya, lasting mor ethan 150k years
Paleocene - Eocene Thermal Maximum
