1/24/17 12 ways to measure time: relative absolute dating (radiometric dating) Principle of faunal succession is
life has changed through time -fossil assemblages are recognizably different
from one another as oo - Relative ages can be determined based on fossil content dans
Geological, or stratigraphic Ranges. uncomformities: non deposited or erosion
Ka thousand years Ma-Million years. Ga-Billion years - Ta-Trillion years Rock record is not always continuous due to erosion/weathering and then re-deposistion.
• Disconformity - Gap in the rock record between
2 parallel layers of sedimentary rock & known by missing fossils in order found
around other noch layers nearby.
• Angular Unconformity - erosional surface on
tilted or folded strata over which younger strata are deposited to Nonconformity - erosionell surface cut into Ligneous or metamorphic rocks, overlain by Isediments
unconformities representi enormous amounts of time without sediment. Comelation of rock units = how geologist put together the time seale..
• Stratigraphic correlationne -tracking rock units of the same age to different areas d room - use surface correlation, well logs fouls lowered into holes that are used in geologic cases), fossils, they beds (coal, ash) Findex Fossils b
• Index fossils
- easy to identify - short lived
•Subsurface correlation when there is not
much geology above ground. Tuse of logging tool-sensors under ground What are absolute dating methods? Henri Bacquerel-discovered radioactivity Ernst Rutherford-discovered half-like and
age dating rocks. Radio Active Decay it. A. Alpha Particle Emission ro v
- loose a He nucleus town B. Electron Capture
-gain an e C. Beta Particle Emission -Lost an e
Radiometric dating Tunstable radioactive elements or isotopes I c parents") change over time into stable products Don't forget about the age old question of zoology study guide
time for 2 of parent to change to daughter -Half-life is unique and constant T-21 billionth of a second to 49 billion years - Decay rates are independent of any outside
influence pressure, temperature) and will happen no matter what and where
1/26/17 mass spectrometer - determination of the Tisotopic abundances required for radiometric dating
Heary isotopes will be less deflected by magnetic field than light isotopes. We also discuss several other topics like umass chemical engineering
Don't forget about the age old question of Reactant means what?
We also discuss several other topics like ● What are the three ways to make a living as an organism?
If you want to learn more check out math 1901
We also discuss several other topics like when hydrogen shares electrons with oxygen, the outermost shell of the hydrogen atoms are full with electrons and oxygen’s valence shell is full with electrons. because the valence shells of these atoms are full, the atoms are stable.
What can be dated? alto olaneous rodes no
-Magma cools -radioactive isotopes build into minerals