Radioisotopic or radiometric dating.pptx

Radioisotopic or radiometric dating

1. 1 Radioisotopic /radiometric dating

2. 2 Radioisotopic/radiometric dating Many believe in an old earth, i.e., billions of years old, due to radioisotopic dating

3. 3 Radioisotopic/radiometric dating Many believe in an old earth, i.e., billions of years old, due to radioisotopic dating But is this really the case? Is it true that the earth is billions of years old?

4. 4 Radioisotopic dating Some basic concepts Carbon 14 40 K- 40 Ar Assumptions Closing slides

5. 5 e - e - e - e - e - e - e - e - e - e - e - e - + + + + + +

6. 6 Three Types of Radioisotopic Decay Gamma radiation – photon of light emitted; atom does not lose mass Alpha radiation – alpha particle has mass; when decay happens atom loses mass

7. 7 Half-life Parent – the original radioactive element Daughter- the resulting element(s) from radioisotopic decay, or series of decay Half-life – the amount of time it takes for parent to decay to 50:50 parent/daughter ratio; e.g., 1,000,000 atoms of 238 U would take 4.5 billion years to get 500,000 atoms each of 238 U and 206 Pb (one half-life); and second 4.5 billion yrs would result in 250,000 atoms of 238 U and 750,000 atoms of 206 Pb (two half-lives)

8. 8 Half-life Parent – the original radioactive element Daughter- the resulting element(s) from radioisotopic decay, or series of decay Half-life – the amount of time it takes for parent to decay to 50:50 parent/daughter ratio; e.g., 1,000,000 atoms of 238 U would take 4.5 billion years to get 500,000 atoms each of 238 U and 206 Pb (one half-life); and second 4.5 billion yrs would result in 250,000 atoms of 238 U and 750,000 atoms of 206 Pb (two half-lives) At this time, unknown what causes an individual radioactive atom to decay while another does not

9. 9 Half-life 206 Pb 206 Pb 206 Pb 206 Pb 206 Pb 206 Pb 206 Pb 206 Pb 238 U 238 U 238 U 238 U 238 U 238 U 238 U 238 U 238 U 238 U 238 U 238 U 238 U 238 U 238 U 238 U 238 U 238 U 238 U 238 U 238 U 238 U 238 U 238 U Parent Daughter ~4,500,000,000 years Parent One half-life

10. 10 Half-life 238 U 238 U 238 U 238 U 238 U 238 U 238 U 238 U 238 U 238 U 238 U 238 U 238 U 238 U 238 U 238 U Parent ~9,000,000,000 years Parent 206 Pb 206 Pb 206 Pb 206 Pb 206 Pb 206 Pb 206 Pb 206 Pb 238 U 238 U 238 U 238 U Daughter 206 Pb 206 Pb 206 Pb 206 Pb Two half-lives

11. 11 206 Pb 238 U 234 Pa 234 Th 230 Th 234 U 214 Po 226 Ra 214 Bi 214 Pb 218 Po 222 Rn Uranium 238 Decay Series 210 Po 210 Bi 210 Pb α α α α α α α α β stable β β β β β 4.47 billion yrs 24 days 20 min 1,602 yrs 77,000 yrs 240,000 yrs 6.7 hrs 27 min 3.1 min 3.8 days 138 days 5 days 22 yrs 0.000164 sec

12. 12 206 Pb 238 U 234 Pa 234 Th 230 Th 234 U 214 Po 226 Ra 214 Bi 214 Pb 218 Po 222 Rn Uranium 238 Decay Series 210 Po 210 Bi 210 Pb α α α α α α α α β stable β β β β β 4.47 billion yrs 24 days 20 min 1,602 yrs 77,000 yrs 240,000 yrs 6.7 hrs 27 min 3.1 min 3.8 days 138 days 5 days 22 yrs 0.000164 sec

13. 13 The late Willard F. Libby led team of scientists at University of Chicago during the post-II War period. 1949 first measured rate of 14 C decay at 5568 ± 30years 1960 Libby received the Nobel Prize in Chemistry Half-life revised to 5730 ± 40 years (Cambridge half-life) 1950’s used Gas Proportional Counting to measure 14 C Liquid Scintillation Counting (LSC) uses benzene, acetylene, ethanol, methanol, and other chemicals. Mid-1970’s development of Accelerated Mass Spectroscopy (AMS) The Atomic Mass Number is the sum of the number of protons and neutrons Carbon 14

14. 14 National Ocean Sciences AMS at Woods Hole Oceanographic Institution, Massachusetts. Photograph of Staff Physicist Robert Schneider placing a carousel of graphite targets into the ion source of the accelerator. Photo by Tom Kleindinst, 1995

15. 15 Air/atmosphere carbon molecules: 98.89% 12 C 1.11% 13 C 0.0000000001% 14 C, or 1 14 C for every 1,000,000,000,000 12 C

16. 16 Air/atmosphere carbon molecules: 98.89% 12 C 1.11% 13 C 0.0000000001% 14 C, or 1 14 C for every 1,000,000,000,000 12 C 12 C is stable

17. 17 Air/atmosphere carbon molecules: 98.89% 12 C 1.11% 13 C 0.0000000001% 14 C, or 1 14 C for every 1,000,000,000,000 12 C 12 C is stable 13 C is stable

18. 18 Air/atmosphere carbon molecules: 98.89% 12 C 1.11% 13 C 0.0000000001% 14 C, or 1 14 C for every 1,000,000,000,000 12 C 12 C is stable 13 C is stable 14 C is unstable; 14 C changes back into 14 N

19. 19 Air/atmosphere carbon molecules: 98.89% 12 C 1.11% 13 C 0.0000000001% 14 C, or 1 14 C for every 1,000,000,000,000 12 C 12 C is stable 13 C is stable 14 C is unstable; 14 C changes back into 14 N Entire inventory of 14 C is called the carbon exchange reservoir .

20. 20 Cosmic Rays Upper Atmosphere Atoms Neutrons Lower Atmosphere 14 N 14 N 14 N 12 C 12 C + neutrons proton 14 C CO 2 CO 2 14 C 12 C 14 C 12 C 14 C 12 C

21. 21 Cosmic Rays Upper Atmosphere Atoms Neutrons Lower Atmosphere 14 N 14 N 14 N 12 C 12 C + neutrons proton 14 C CO 2 CO 2 14 C 12 C 14 C 12 C 14 C 12 C

22. 22 Cosmic Rays Upper Atmosphere Atoms Neutrons Lower Atmosphere 14 N 14 N 14 N 12 C 12 C + neutrons proton 14 C CO 2 CO 2 14 C 12 C 14 C 12 C 14 C 12 C

23. 23 Cosmic Rays Upper Atmosphere Atoms Neutrons Lower Atmosphere 14 N 14 N 14 N 12 C 12 C + neutrons proton 14 C CO 2 CO 2 14 C 12 C 14 C 12 C 14 C 12 C

24. 24 Cosmic Rays Upper Atmosphere Atoms Neutrons Lower Atmosphere 14 N 14 N 14 N 12 C 12 C + neutrons proton 14 C CO 2 CO 2 14 C 12 C 14 C 12 C 14 C 12 C

25. 25 Cosmic Rays Upper Atmosphere Atoms Neutrons Lower Atmosphere 14 N 14 N 14 N 12 C 12 C + neutrons proton 14 C CO 2 CO 2 14 C 12 C 14 C 12 C 14 C 12 C

26. 26 Cosmic Rays Upper Atmosphere Atoms Neutrons Lower Atmosphere 14 N 14 N 14 N 12 C 12 C + neutrons proton 14 C CO 2 CO 2 14 C 12 C 14 C 12 C 14 C 12 C

27. 27 Cosmic Rays Upper Atmosphere Atoms Neutrons Lower Atmosphere 14 N 14 N 14 N 12 C 12 C + neutrons proton 14 C CO 2 CO 2 14 C 12 C 14 C 12 C 14 C 12 C

28. 28 Cosmic Rays Upper Atmosphere Atoms Neutrons Lower Atmosphere 14 N 14 N 14 N 12 C 12 C + neutrons proton 14 C CO 2 CO 2 14 C 12 C 14 C 12 C 14 C 12 C

29. 29 Known limitations Size of sample is important. the larger the better purification and distillation removes some matter (LSC) AMS better able to handle smaller samples Requires great care in collecting and packaging. Carbon sample location requires careful stratigraphic examination. Upper practical limit of 40,000 – 50,000 years, or 9 -10 half-lives. Atmospheric 14 C / 12 C ratio not always constant. In general, single dates should not be trusted. Whenever possible multiple samples should be collected and dated from associated strata. (http://id-archserve.ucsb.edu/Anth3/Courseware/Chronology/08_Radiocarbon_Dating.html#C14Process)

30. 30 Other factors affecting 14 C dating Plants may discriminate against intake of 14 C; plants are known to discriminate against 13 C 1 1 . www.plantphys.net/article.php?ch=9&id=135

31. 31 Other factors affecting 14 C dating Plants may discriminate against intake of 14 C; plants are known to discriminate against 13 C 1 Reservoir effects 1 . www.plantphys.net/article.php?ch=9&id=135

32. 32 Other factors affecting 14 C dating Plants may discriminate against intake of 14 C; plants are known to discriminate against 13 C 1 Reservoir effects Suess or Industrial effect 1 . www.plantphys.net/article.php?ch=9&id=135

33. 33 Other factors affecting 14 C dating Plants may discriminate against intake of 14 C; plants are known to discriminate against 13 C 1 Reservoir effects Suess or Industrial effect Atomic bomb effect 1 . www.plantphys.net/article.php?ch=9&id=135

34. 34 Other factors affecting 14 C dating Plants may discriminate against intake of 14 C; plants are known to discriminate against 13 C 1 Reservoir effects Suess or Industrial effect Atomic bomb effect Noah’s flood 1 . www.plantphys.net/article.php?ch=9&id=135

35. 35 14 C in coal C14 found in coal supposedly millions of years old

36. 36 14 C in fossils C14 found in fossilized wood

37. 37 14 C in diamonds Diamonds are believed to have formed 1-3 billion years ago The earth’s mass is about 6x10 27 g, which would be equivalent to about 4.3x10 26 atoms of 14 C It takes 88 half-lives to get to a single atom of 14 C 88 half-lives is about 500,000 years.

38. 38 The presence of 14 C in supposedly ancient coal, fossil wood, and diamonds falsifies the notion that the rocks or strata in which they were found are millions or years old.

39. 39 K-Ar dating

40. 40 K-Ar dating Parent daughter 40 K 40 Ar 40 Ca

41. 41 K-Ar dating Parent daughter 40 K 40 Ar 40 Ca Half-life of 40 K is 1.26 billion years.

42. 42 K-Ar dating Parent daughter 40 K 40 Ar 40 Ca Half-life of 40 K is 1.26 billion years. 40 Ca is rarely used to determine dates because it is hard to determine the quantity of calcium initially present.

43. 43 K-Ar dating Parent daughter 40 K 40 Ar 40 Ca Half-life of 40 K is 1.26 billion years. 40 Ca is rarely used to determine dates because it is hard to determine the quantity of calcium initially present. 11.2% of 40 K decays to 40 Ar

44. 44 K-Ar dating Parent daughter 40 K 40 Ar 40 Ca Half-life of 40 K is 1.26 billion years. 40 Ca is rarely used to determine dates because it is hard to determine the quantity of calcium initially present. 11.2% of 40 K decays to 40 Ar 88.8% of 40 K decays to 40 Ca

45. 45 Whole rock dating – the whole of the rock sample is crushed and dated Partial rock dating – rocks are generally composed of different minerals; these different minerals have different structures and radioisotopes behave differently in each mineral Note: radioisotopic dating is usually done on igneous and volcanic rock. Metamorphic and sedimentary rocks are considered less suitable for dating because their origin is already preexisting and re-worked rock

46. 46 Date calculation: t = h x ln[1 + ( 40 Ar)/(0.112 x ( 40 K))]/ln(2) where: t = time in years h = half-life in years ln = natural logarithm

47. 47 Atmosphere (air) contains 40 Ar -some air 40 Ar may be trapped in rocks -ratio of 40 Ar to 39 Ar in air is well known at 295:1 -measuring 39 Ar and 40 Ar, and applying the ratio one can subtract off air- 40 Ar

48. 48 Measured K-Ar, Mt. St. Helens http://www.answersingenesis.org/tj/v10/i3/argon.asp

49. 49 Measured K-Ar, Mt. St. Helens Lava solidified in 1986 http://www.answersingenesis.org/tj/v10/i3/argon.asp

50. 50 Measured K-Ar, Mt. St. Helens Lava solidified in 1986 340,000 years ± 600 yrs http://www.answersingenesis.org/tj/v10/i3/argon.asp

51. 51 Measured K-Ar, Mt. St. Helens Lava solidified in 1986 340,000 years ± 600 yrs 2,800,000 yrs ± 600,000 yrs http://www.answersingenesis.org/tj/v10/i3/argon.asp

52. 52 Measured K-Ar, Mt. St. Helens Lava solidified in 1986 340,000 years ± 600 yrs 2,800,000 yrs ± 600,000 yrs Critics claim excess Ar, which is known about http://www.answersingenesis.org/tj/v10/i3/argon.asp

53. 53 Measured K-Ar, Mt. St. Helens Lava solidified in 1986 340,000 years ± 600 yrs 2,800,000 yrs ± 600,000 yrs Critics claim excess Ar, which is known about Biblical creationists question whether dating works on rocks of unknown ages when it does not work on rocks of known age http://www.answersingenesis.org/tj/v10/i3/argon.asp

54. 54 Half-lives of other radioisotopes Most half-lives taken from Holden, N.E. (1990) Pure appl. Chem. 62 , 941-958. Radioactive Isotope (Parent) Product (Daughter) Half-Life (Years) Samarium-147 Neodymium-143 106 billion Rubidium-87 Strontium-87 48.8 billion Rhenium-187 Osmium-187 42 billion Lutetium-176 Hafnium-176 38 billion Thorium-232 Lead-208 14 billion Uranium-238 Lead-206 4.5 billion Potassium-40 Argon-40 1.26 billion Uranium-235 Lead-207 0.7 billion Beryllium-10 Boron-10 1.52 million Chlorine-36 Argon-36 300,000 Carbon-14 Nitrogen-14 5715 Uranium-234 Thorium-230 248,000 Thorium-230 Radium-226 75,400

55. 55 Some assumptions Decay rate is constant over the determined time period

56. 56 Decay rate did not change when subject to extreme changes in temperature, pressure, magnetism, electrical fields and chemical alteration.

57. 57 Constant decay rate? Anderson and Spangler showed decay process is not random, therefore, concluded that decay rate is uncertain, putting all radiometric dating into serious question. Working with Cobalt 60 and Cesium 137 they state “The evidence is inconsistent with the theory of decay independence.” 1 Cobalt 60 was significantly influenced by electrical field. “…even though holding responsible scientific positions, these authors admitted to difficulty in getting their work published and since then have confessed that it has been ‘disregarded, discounted, disbelieved…by virtually the entire scientific community’ (Anderson and Spangler, 1974)” 2 1 Quoted in Note 11, In the Minds of Men , Ian T. Taylor, TFE Publishing:Toronto, Canada, 3 rd edition, fifth reprint 1994; p. 457. 2 Taylor, ibid ., p. 296.

58. 58 In cautiously worded terms Anderson and Spangler “writing in American Physical Society Bulletin , 1971, 10:1180 had presented their data to show that the gamma emission rate of cobalt 60 was significantly influenced by electrical fields. They concluded that, in this case, radioactive decay is not independent.” 1 In 1974, the authors freely expressed their views more explicitly in the, now defunct, journal Pens ée. 1 Taylor, op cit ., p.457.

59. 59 Rhenium-187 1 -half-life of 42 billion years -half-life of 33 years when stripped of electrons -isolated case 1. Don DeYoung, Thousands…Not Billions, p. 144, with reference to Kerr, Richard, 1999, Tweaking the Clock of Radioactive Decay, Science 286(5441), 882-883 .

60. 60 Solar neutrinos -seasonal fluctuations -rates increased when closer to the sun and decreased when farther from the sun Brian Thomas, http://www.icr.org/articles/radioactive-decay-rates-not-stable, article posted August 4, 2009; referencing Mullins, J., 2009, Solar ghosts may haunt Earth’s radioactive atoms, New Scientist , 2714:42-45.

61. 61 Cavitation -shock waves produced from the collapse of vapour bubbles resulting from extremely fast water flows -during a 90-minute experiment, radioactive thorium decay was accelerated by a factor of 10,000 times Brian Thomas, http://www.icr.org/articles/radioactive-decay-rates-not-stable, article posted August 4, 2009; referencing Cardone, F., R. Mignani and a. Petrucci, 2009. Piezonuclear decay of thorium. Physics Letters A . 373 (22): 1956-1958.

62. 62 Radioisotopes not found on earth Old earth suggested from extinct parent isotopes for which there is strong evidence that these once existed in substantial amounts in meteorites, but have since completely decayed away. Extinct Isotope Half-life (years) Plutonium-244 82 million Iodine-129 16 million Palladium-107 6.5 million Manganese-53 3.7 million Iron-60 1.5 million Aluminum-26 700,000 Calcium-41 130,000 However, can be interpreted as vast quantity of decay occurred in the past, not necessarily indicative of age .

63. 63 The present

64. 64 Deep Earth Zircons Uranium/lead age of 1.5 billion yrs ± 20 million yrs Crystals contained too much helium to be million yrs old Leak rate of helium out of zircon crystals was unknown Predicted and measured helium leak rates agreed at ~6000 yrs Helium leak rate concords with Biblical history D. Russell Humphreys, A Tale of Two Hourglasses, Impact article #402, Institute for Creation Research, California, December 2006.

65. 65 http://creationontheweb.com/content/view/6193/ accessed December 01, 2008. Predicted Leak Rates

66. 66 http://creationontheweb.com/content/view/6193/ accessed December 01, 2008.

67. 67 Some assumptions Decay rate is constant over the determined time period Neither parent nor daughter material has been added to or taken away from the sample during the determined time period

68. 68 238 U 238 U 238 U 238 U 238 U 238 U 206 Pb 238 U 238 U 238 U 238 U 206 Pb 238 U 238 U 238 U 238 U 206 Pb 206 Pb 206 Pb 206 Pb 206 Pb 206 Pb 206 Pb 206 Pb 238 U 238 U 238 U 206 Pb 238 U 238 U 238 U 238 U ~ 4.5 billion years 206 Pb 238 U 238 U 206 Pb 206 Pb 206 Pb 238 U Time Now

69. 69 Some assumptions Decay rate is constant over the determined time period Neither parent nor daughter material has been added to or taken away from the sample during the determined time period The initial parent/daughter ratio is known (i.e., it is most often assumed to be zero daughter)

70. 70 Argon-Argon 40 K- 39 K ratio appears to be constant in the sample Sample put in nuclear reactor and bombarded with neutrons 39 K is turned into 39 Ar Assumed that newly formed 39 Ar is proportional to 39 K

71. 71 Wiens calls this a typical argon-argon plot. But is it typical? Notice also, the Y-axis on the left hand side. From where does one obtain the age? Roger C. Wiens, Radiometric Dating A Christian Perspective , revised 2002. Wiens has a PhD in physics with a minor in geology. He is a firm believer in the radiometric dating method and believes in an old earth.

72. 72 Isochrons Iso = same, equal chron = time Attempts to address issue of initial amount of daughter material before any parent material had time to decay Attempts to address issue of addition or subtraction of external radioisotopic material, i.e., whether or not the sample remained a closed system Attempts to address the most likely computed age of a rock sample, based upon the statistical average of several radioisotope measurements

73. 73 An ideal isochron Parent isotope, Rb-87/Sr-86 Daughter isotope, Sr-87/Sr-86 Mineral 1 Mineral 2 Mineral 3 Mineral 4 Rock when formed Rock now

74. 74 Fig. 5. A thin vertical amphibolite layer (darker rock) just upstream of Clear Creek, Grand Canyon. Creation 27 (3) June-August 2005, p. 46.

75. 75 Creation 27(3) June-August 2005, p. 47.

76. 76 Creation 27 (3) June-August 2005, p. 47.

77. 77 “It would not be inconsistent with the scientific evidence to conclude that God made everything relatively recently, but with the appearance of great age, just as Genesis 1 and 2 tell of God making Adam as a fully grown human (which implies the appearance of age). The idea of a false appearance of great age is a philosophical and theological matter that we won't go into here. … Roger C. Wiens, Radiometric Dating A Christian Perspective , revised 2002. Wiens has a PhD in physics with a minor in geology. He is a firm believer in the radiometric dating method and believes in an old earth.

78. 78 … The main drawback—and it is a strong one—is that this makes God appear to be a deceiver. However, some people have no problem with this. Certainly whole civilizations have been incorrect (deceived?) in their scientific and theological ideas in the past. Whatever the philosophical conclusions, it is important to note that an apparent [ emphasis added ] old Earth is consistent with the great amount of scientific evidence.” Roger C. Wiens, Radiometric Dating A Christian Perspective , revised 2002. Wiens has a PhD in physics with a minor in geology. He is a firm believer in the radiometric dating method and believes in an old earth.

79. 79 However, if God stated that He created in six days, but really took millions and billions of years, would this not make God a deceiver? If God really took millions and billions of years to make the heavens, earth, and all creatures, but He said He did it in six days, would this not make God incompetent at communicating?

80. 80 Age is not directly measured Amount (or ratio) of parent/daughter, at the present time, is what is measured Heat, pressure, water, chemicals can affect the parent/daughter ratio

81. 81 Other dating methods Thermoluminescence (TL): when individual grains of common minerals, such as quartz, are heated, they emit light, and this is related to the radiation ‘stored’ in the crystal structure. By measuring the light emitted from the mineral grain when it is heated, and measuring the radiation in the environment where the grain was found, a date is calculated. It is assumed that the radiation was slowly absorbed from the environment, building up from zero at a certain time in the past (perhaps when the grain was last exposed to sunlight). Optically-stimulated luminescence (OSL): dates are based on exactly the same principle and TL. But instead of heating the grain, it is exposed to light to make it emit its ‘stored’ radiation. The calculated date is based on the same assumptions, and affected by the same uncertainties, as for TL . Electron-spin resonance: dates are based on the same principles as TL and OSL. However, the ‘stored’ radiation in the sample is measured by exposing it to gamma radiation and measuring the radiation emitted. The measuring technique does not destroy the ‘stored’ radiation (as does TL and OSL), so the measurement can be repeated on the same sample. The calculated date is based on the same assumptions, and affected by the same uncertainties, as for TL and OSL .

82. 82 Other dating methods cont’d Thorium-uranium (Th/U) dates are based on measuring the isotopes of uranium and thorium in a sample. It is known that uranium-238 decays radioactively to form thorium-230 (through a number of steps, including through uranium-234). The dating calculation assumes that the thorium and uranium in the sample are related to each other by radioactive decay. Furthermore, before a date can be calculated, the initial ratios of 230Th/238U and 234U/238U need to be assumed, and it is also assumed that there has been no gain or loss of uranium or thorium to/from the environment—i.e. that the system is ‘closed’. However, the bone and soil must have been ‘open’ to allow these elements to enter and accumulate. Protactinium-uranium (Pa/U) dates are based on similar principles as Th/U dating, but use uranium-235 and protactinium-231 instead. The isotope 235U decays radioactively to form 231Pa. Again, it is assumed that the isotopes in the sample are related to each other by radioactive decay. Also, the initial ration of 231Pa/235U has to be assumed, and it is assumed that there has been no gain or loss of uranium or protactinium to for from the environment—i.e. that the system is ‘closed’. Again, any bone sample containing uranium must have been ‘open’ to allow it to accumulate in the first place.

83. 83

84. 84 Eisegesis

85. 85 Exegesis

86. 86 Scientist & Bible

87. 87 “When Moses wrote that God created Heaven and Earth and whatever is in them in six days, then let this period continue to have been six days, and do not venture to devise any comment according to which six days were one day. … Martin Luther cited in E. Plass, What Martin Luther Says: A Practical In-House Anthology for the Active Christian, Concordia Publishing House, St. Louis, 1991, p. 1523

88. 88 But, if you cannot understand how this could have been done in six days, then grant the Holy Spirit the honor of being more learned than you are. For you are to deal with the Scripture in such a way that you bear in mind that God Himself says what is written. But since God is speaking, it is not fitting for you wantonly to turn His Word in the direction you wish to go.” Martin Luther cited in E. Plass, What Martin Luther Says: A Practical In-House Anthology for the Active Christian, Concordia Publishing House, St. Louis, 1991, p. 1523

89. 89

90. 90 Acknowledgments Answers In Genesis Creation Ministries International Institute for Creation Research

91. 91 The End