1. Earth’s History

3. A fossil is ________________________________________________
The remains or the evidence of a living thing

4. 3. Fossils indicate that many different life forms existed at one point
They are now extinct.

5. How do you think they lived?
Example: fossil teeth
give clues about the
kind of food the animal
ate

6. What is happening to this organism ? _________________
Evolved over time

7. NY was warmer and under water
Fossils found in NYS ___________________________________________
NY was warmer and under water

8. The age of a rock/event in relation to the age of other rocks/events
. Relative Age-
_________________________________________________________________
Original Horizontality-
____________________________________
. Principle of Superposition- ________________________________________________________________________________________________
The age of a rock/event in relation to the age of other rocks/events
All rock layers originally laid down flat
Bottom layer rock is oldest, top layer is youngest. (undisturbed layers only)

9. Buried eroded surface (missing rock layer)
E. Unconformity- ________________________________________________________
Unconformities represented by:
: wavy line
: bolded line
Buried eroded surface (missing rock layer)

10. Deposition of rock layers Uplift,
Folding
Deposition of rock layers
Uplift,
Weathering & erosion
Submergence & New Deposition
animation

11. All rock layers are laid down ________ before they are affected.
All rock layers are ________ than the event
first
older

12. ______________________
Intrusion-
______________________
Extrusion-
____________
_________________________
forcing a body of igneous rock between or through existing formations, without reaching the surface.
the movement of
Magma onto the
surface of the
Earth, forming
igneous rock

13. siltstone shale siltstone fault folding sandstone limestone shale
Igneous intrusion
siltstone

14. Y ___________ ____________ ___________ ___________O_________
Unconformity
intrusion
Fault
sandstone
Conglomerate
Shale
Limestone
shale
Conglomerate
Unconformity
Fold
Limestone

18. 3. 4.

22. F. Index Fossils- ______________________________________________________________
1. ______________________________
________________________________
2. ______________________________
A fossil that is used to date the rock layers in which it is found
The organism must have lived over a wide geographical area, large horizontal distribution
The organism must have existed for a relatively short time, small vertical distribution

23. Volcanic Ash -
Is used as a geological time marker because
- Spreads over a wide area
- Deposits relatively quickly

26. Absolute Age- ____________________________________________________________________________
Radioactive Decay
1. __________________= an atom that has an unstable nucleus that changes spontaneously, or “decays”
2. __________________= the stable elment that is the result of the spontaneous change in a radioactive element.
The measure of how many years old an event occurred or an organism lived
Radioactive/parent
Decay/daughter

27. 3. Half-life= _______________________________________________________
4. The rate of decay (the half-life period of time) is NOT affected by any outside condition such as:
The time required for half of the atoms to decay
-Temperature
-Size
- Moisture
- Pressure

29. 4.9 x 1010 1.3 x 109 Argon 40 or Calcium 40 Sr-87 Rubidium-87
Radioactive Element
Half-life (years)
Decay Element
Potassium-40
4.9 x 1010
Lead-206
Carbon-14
1.3 x 109
Argon 40 or Calcium 40
1,300,000,000
Sr-87
Rubidium-87
Uranium-238
4.5 x 109
Nitrogen-14
5.7 x 103

30. 5. _________ has a short half-life and is therefore used to date the remains of _______________ such as____________________________
Carbon-14
organic RECENT matter
petrified wood, bones, leather, teeth