1. Geologic Time Earth’s History

2. Uniformitarianism The past is the key to the future Processes that happen today are the same processes that happened in ancient times Modern Ripples Fossilized Ripples Modern Mudcracks Fossilized Mudcracks

3. Dating – 2 types Relative Dating Absolute Dating – Know order of events but not dates – Know exact age

4. Relative Dating – Key Concepts Law of Superposition Principle of Original Horizontality Principle of Cross-Cutting Relationships Inclusions

5. Law of Superposition Each bed is younger than the bed below it.

6. Principle of Original Horizontality Sedimentary layers are deposited horizontally

7. Principle of Cross-Cutting Relationships Faults and intrusions are younger than the rocks they cut through

8. Inclusions Fragments of one rock unit that have been enclosed within another are older

9. Relative Dating Youngest  G A B C F D Oldest  E

10. Conformable Beds Beds that have not been disturbed

11. Uncomformities – Angular – Disconformity – Nonconformity Substantial break or gap in the rock record 3 types

12. Angular Unconformity Older layers have been deformed, eroded, and younger layers deposited above

13. Disconformity Beds are parallel relative to each other but there is a break in sequence Implies a cessation of sedimentation or erosion, but no tilting Hard to recognize

14. Nonconformity Sedimentary layers overlie igneous or metamorphic layers

15. Unconformities 1. Surface 1 is an example of ?Nonconformity 2. Surface 2 is an example of ? Angular unconformity 3. Surface 3, 4 and 5? Disconformity 4. Granite is _________ than the Schist.Younger Question:Answer:

16. Absolute Age It is the age of a rock unit, fossil or geologic event expressed in units, such as years For example, your birthday... – You were born on a specific day, month and year Absolute age can be determined by Radioactive Decay

17. Radioactive Decay - The Atom Fundamental unit of matter. Made up of components called subatomic particles. – Protons (positive charge) – Neutron (no electrical charge) – Electron (negative charge)

18. Radioactive Decay - Stable Isotopes An atom is generally stable if the number of protons equals the number of neutrons in the nucleus.

19. Radioactive Decay - Carbon Isotopes Carbon-14 also referred as: Types of carbon – C-14 – Radiocarbon – C-12 (stable) – C-13 (unstable) – C-14 (unstable)

20. Radioactive Decay The nucleus of an atom (decays) changes into a new element. 14 C  14 N 67 How long does this take? The proton number (atomic number) changes.

21. Carbon-14 and Its Half-Life The rate of decay is a measure by how long it takes for half an element to decay The half life of C-14 is 5,730 years

22. How is Carbon-14 Made?

23. When Does the Clock Start? When a plant or animal dies, the clock starts. Organism dies No more C-14 intake C-14 begins to decay

24. How the Carbon Clock Works There are two types of carbon used in the dating process A living starfish has the same ratio as the atmosphere A fossilized starfish has a different ratio – C-12 (stable  does not decay) – C-14 (radioactive  decays) When an organism is alive, it has the same ratio (C-12 to C-14) that is found in the atmosphere (1 trillion to 1)

25. How the C-12/C-14 Ratio Works Amount of stable C-12 Amount of unstable C-14 RatioYears dead# of half-lives 100 trillion1001-T to 100 100 trillion502-T to 15,7301 100 trillion254-T to 111,4602 100 trillion12.58-T to 117,1903 100 trillion616-T to 122,9204 100 trillion332-T to 128,6505 Carbon-14 can date elements up to approximately 100,000 years.

26. C-14 Example Turin Shroud Believed to be the burial cloth of the crucified Christ.

27. Example Turin Shroud An artistic impression matching the images above (right)

28. Example Shroud of Turin Evidence: –Blood Stains –Wounds –Weave of cloth –Pollen grains –Serum albumin Skeptics: –Painting –Blood - red

29. Carbon-14 Results Carbon-14 dates the Turin Shroud to: 1356 A.D. When was Jesus born? Is the Shroud authentic?

30. More Examples Dead Sea Scrolls Qumran Caves Aerial viewCaves

31. More Examples Dead Sea Scrolls Fragment of Dead Sea Scroll Dead Sea Scrolls were found in jars Evidence: >500 manuscripts. 15,000 fragments that describe every book of the Old Testament. Some Papyrus samples bear exact dates w/in text that coincide with C-14 results. Skeptics: Some of the scrolls appear to be work of early Christians.

32. Carbon-14 Results Carbon-14 pre-dates Christianity: 150 B.C – 5 B.C.

33. One More Example Solomon’s Temple Stone Tablet Evidence: Confirms the existence of Solomon’s Temple – 9 th Century B.C. 10 lines of Phoenician script describing the life of King Jehoash. Repair to temple. War Etc.

34. Carbon-14 results It’s authentic! Carbon-14 dates stone tablet to: 9 th Century B.C.

35. Carbon-14 Inconsistencies In 1993, scientists found wood (trees) buried in basalt flows (69 feet deep). Wood samples sent to two laboratories to be carbon-14 dated 44,000 years old. Basalt sent to two laboratories to be potassium-argon dated 45,000 million years. 69 feet deep Wood encased in basalt

36. Known Carbon-14 Inconsistencies Mollusks that are living dated at 2,300 years Seal skins (fresh) dated 1,300 years

37. Important Questions You be the judge!! Are these true biblical artifacts or just plain old relicts?

38. Important Radioactive Isotopes In Geology ParentDaughterHalf-lifeUseful dating range (years) Typical Minerals Uranium 238Lead 2064.5 billion years 10 million to 4.6 billion Zircon Uraninite Uranium 235Pb 207713 million years 10 million to 4.6 billion Zircon Uraninite Thorium 232Pb 20814.1 billion years 10 million to 4.6 billion Zircon Uraninite Potassium 40Argon 40 & Calcium 40 1.3 billion50,000 - 4.6 billion Whole volcanic rock Rubidium 87Strontium 8747 billion years10 million - 4.6 billion Metamorphic/ igneous rock Carbon 14Nitrogen 145730 years100-100,000Organic materials