Lesson 3b: Absolute Time Flashcards
What was Archbishop James Ussher’s contribution to absolute time?
Volume 4: Annals of the World; Earth was created in 4004 B.C.E
What were James Hutton’s contributions to absolute time? 3
- Introduced the idea of Geological (Deep Time); Earth is millions of years old, not thousands
- Repeated cycles of uplift and erosion were found in the land’s geology.
- Wrote the Theory of Earth; the foundation of modern geology
What was Henri Becqurele’s contribution to absolute time?
Discovered radioactivity in uranium in 1896
What was Ernst Rutherford’s contribution to absolute time?
Discovered the cause of radiation (radioactive decay); Earth 700 Ma old
What was Cameron Patterson’s contribution to absolute time?
Used uranium-lead isotope on several meteorites; Earth is 4.55+/- 0.07 billion years old
What is radiometric dating?
A way of directly dating rocks that contain a radioactive isotope
What is radiocarbon dating?
A way of dating organic matter using a radioactive isotope Carbon-14
What is a half-life?
The amount of time required for half of the radioactive isotope to decay.
What is the Geologic Time Scale
- Eons - geological time
- Eras - what eons are divided into
- Periods - what eras are divided into
- Epoch - what periods are divided into
What is radioactivity?
The spontaneous decay in the structure of an atom’s nucleus
What are the 4 categories of eons? (Oldest to youngest)
- Hadean - oldest
- Archean - ancient
- Proterozoic - before life
- Phanerozoic - visible life
What eon do we currently live in?
Phanerozoic
What are the 3 categories of eras? (Oldest to youngest)
- Paleozoic era - oldest
- Mesozoic era - middle life
- Cenozoic era - new or recent life
What era are we currently in?
Cenozoic era
What are the 3 categories of periods? (Oldest to youngest)
- Paleogene - oldest
- Neogene
- Quaternary (Present)
