Changing Views of the History of the Earth. Contents. Introduction. If, in the year AD 1. European how old the planet Earth was and to recount its. Genesis. If you asked the same question of an educated European. AD 1. 90. 0 you would have received a quite different. He would have answered that the Earth was ancient. Noachian flood, and that the. Earth. In short, Genesis was an allegory and not literal. The story of this great change in the conception of the. Earth is not a simple one. The chronicle of this. The. pre- scientific period before AD 1. In the. pre- scientific era the Biblical account and the. Greek philosophers were accepted. In this period a number of comprehensive. We know the Earth is old. But how do we know its age? The Universe, Cosmos, Galaxies, Space, Black Holes, Earth, Planets, Moon, Stars, Sun Solar System. These were long on armchair. This period was. marked by a great deal of field geology rather than grand. It became clear that there had been. Earth's topography over time and. Noachian flood. Notable observations. Science in Christian Perspective. A Christian Perspective. Wiens 941 Estates Drive, Los Alamos, NM 87544 [email protected].This document discusses the way radiometric dating is used to establish the conventional geological time scale. It mentions a geologically complicated example, used. Rock, in geology, naturally occurring and coherent aggregate of one or more minerals. Such aggregates constitute the basic unit of which the solid Earth is comprised. Start studying Chapter 6 Rocks and Fossils. Learn vocabulary, terms, and more with flashcards, games, and other study tools. It is the third-largest moon in the Solar System and the largest. Studies of strata suggested that they were laid down by. Studies of earthquakes and volcanoes showed that the. Observation of rain, wind, water erosion, and sea. The. catastrophist- uniformitarian debate ran from about. By the end of the 1. Earth had a long and varied history. Interest in. major cosmogony was revived. The major debate was between. Cuvier, who held that the history. Earth was dominated by major catastrophic revolutions. Hutton and Lyell, who held. Earth was dominated by slow relatively. Earth with a static over all history. The efforts of the. Science. The modern. AD 1. 85. 0 to the present. The great. debate was won by the uniformitarians, so much so that the. The modern period has. Earth and the. processes that have acted during that history. Many authors choose to present the history of a complex. I have chosen. instead to provide a chronology of significant works and. Geology changed over time. The selections. and comments here are not a complete exposition of the. Estimates of the Age of the. Earth. In Europe the issue of the age of the Earth was not a. Earth was assumed to be accounted for in Genesis. The. rise of science produced a major change in attitude. In the pre- scientific world view the issue of the age of. Earth was a theological question. The account in. Genesis is replete with miracles that do not stand up under. This did not matter; the theological. It. was not ruled out, per se, but it was not necessary. It was. not part of the attitude. In the new science, however. Ussher and Descartes. In 1. 64. 0 Ussher produced. Earth was created in 4. BC. In 1. 63. 7 Descartes produced a cosmogony that was highly. What was the. difference? It was not in their estimates of the age of the Earth - . Descartes retained the biblical date. Ussher accepted the. Biblical account at face value, relying on the Biblical. He implicitly. assumed that the world was created much as it is now. His account was plausible by the immature. Science of his times; however it quite. Biblical account of a. In the 1. 70. 0's belief in. Earth crumbled. Attempts to calculate the. Earth from physical considerations yielded. Buffon, 1. 77. 4) to. Maillet, Buffon). The physical models were open to question and, in. The geological evidence was more. It became quite clear that many areas of the Earth. Earth. everywhere. By the early 1. 80. Earth had a long history. The uniformatarians. Hutton 1. 78. 8, Lyell 1. Earth as being. indefinitely old. The catastrophists (Cuvier 1. Beaumont 1. 85. 2. Buckland 1. 83. 6) accepted that the Earth was old; they. There was no single. Earth's age in the mid 1. There were various attempts to. Earth's age, working back from sedimentation. The attempts. produced estimates from about 1. There were two major problems with. The first is that the geological history was. The second is that the rates of. In the late 1. 80. Descartes, made new. Earth and the Sun. There were. two basic questions they asked: How long would it take for. Earth to cool from its initial heat of formation to its. Sun been shining. In 1. 86. 2 Kelvin estimated. Earth to be 9. 8 million years, based on a. This was a minimum acceptable. Later in 1. 89. 7 he revised his. This was too. short for the geologists to swallow. Estimates of the age. Sun were also too small to be consistent with. Kelvin did not know about radioactivity and heating of. Earth's crust by radioactive decay; for this reason his. Likewise, it wasn't until. Einstein's theory of relativity was developed that there. Sun could have been. Prior to the development of radiometric dating. Radiometric dating permits. The first. radiometric dating was done in 1. Earth was several billion. Currently the best estimate of the age of the. Earth is 4. 5. 5 billion years. An extensive chronology of the. Chronology of radiometric. It should be understood that estimating the ages of. C- 1. 4) method for dating. Radiometric dating of rocks is based on. Potassium, Thorium, and. Uranium. Radiocarbon dating is based on the decay of the. C- 1. 4 isotope and is irrelevant to determining. Earth. Chronology of Writings 1. Leonardo Da Vinci: Selections from the Notebooks of Leonardo Da. Vinci. In his notebooks Da Vinci ponders fossil. Noachian flood. In the mountains of Parma and. Piacenza multitudes of shells and corals with holes may be. Le Roy accepted that land. Le Roy was vague about. He can be considered as a very early. Nathaniel Carpenter: Geography delineated forth in two. Bookes In this early work Carpenter argued that the. Flood could not have been the major agent of geological. Simon Stevin: Second Book of Geology. Stevin. followed up Le Roy with arguments that wind and water. Rene Descartes: Discours de la Methode. Descartes. constructed a history of the Earth which was quite. Some of the main points of his system were. Earth formed as a fiery ball, that when it cooled. James Ussher: A number of writers. Biblical. chonologies, astronomical records, and historical. Of these, Ussher's date of 4. BC is the. most famous. Other dates include 3. BC (John Lightfoot. AD 1. 64. 4) and 5. BC (Theophilus of Antioch. Nicholas Steno: The Produmus. From his field observations of the Tuscan landscape. Flood was important but did not. Thomas Burnet: Sacred Theory of the Earth. Burnet's. famous and widely read book reworked Descartes's. In his conception. Earth was a smooth ovoid. Over time the. surface dried out and the abyssal waters were heated. John Ray: The. Wisdom of God Manifested in the Works of Creation. One of the notable. Ray's works was the thought he put into. Ray accepted. that there had been continuous interchange between land and. Baron Leibnitz: Protogea. Leibnitz reworked. Descartes's cosmogony. Protogea was published much later in. John Woodward: An essay toward a Natural History of the. Earth. Woodward came down fairly strongly for the. God that could not be. He also. postulated hydrological sorting to account for the ordering. William Whiston: A new theory of the Earth.. Whiston. added comets to Burnet's cosmogony as the source of the. Robert Hooke: Lectures and Discourse of Earthquakes and. Subterranean Eruptions. Hooke believed that the. Flood. Using Descartes's cosmology, the assumption. Peter Pallas: Observation sur la Formation des. Montagnards.. Pallas made extensive observations. Russian mountains. He observed the results of processes. He. argued for occasional catastrophic events as an origin for. Comte de Buffon: Epochs of Nature. Buffon assumed that. He himself was suspicious that this was much too. Jean de Luc: Lettres Physique et Morales sur l'Histoire de. Terre et de l'Homme. Whitehurst added the notion of drastic tidal. Woodward's cosmogony. Horace- Benedict de Saussure. Voyages dans les Alpes. De. Saussure made extensive observations of the Alps. He. appreciated that curved strata had originally been laid. Abraham Werner: Kurze Klassification und Beschreibung der. Gebirgsarten. Werner recognized the. Earth. 1. 78. 8James Hutton: Theory of the Earth; or, an investigation of. Hutton is. traditionally credited with being the father of modern. He was the first modern uniformitarian. Hutton. argued that the Earth was of immense antiquity, cycling. The. last sentence of Hutton's 1. The result, therefore, of our present enquiry is. Robert Townson: Philosophy of Mineralogy. Townson was. one of the many catastrophists of the late 1. He pointed out that fieldwork had revealed. Earth could not be. Creation and catastrophic flood. Richard Sullivan: A View of Nature. Sullivan was another. He wrote. Thus succeed revolution to revolution. When the masses. of shells were heaped upon the Alps, then in the bosom of. The sea announces everywhere its different. Robert Kirwan: Geological Essays. Kirwan was a. scriptural geologist. Although he mostly followed the. Earth took several centuries. Kirwan's. virulent attacks on Hutton had the effect of making Hutton. James Hall: Transactions of the Royal Society of. Edinburgh. Hall argued that Hutton's water cycles. Alps. He proposed huge waves on a catastrophic scale that. Baron de Cuvier: Dicours sur les Revolutions du Globe. His extensive researches in the geology of. Paris basin led him to postulate a series of many. William Buckland: Vindiciae Geologicae. In 1. 82. 0 Buckland. Thus he wrote. Again the grand fact of an universal deluge at no very. Scripture, or any other authority, Geology of itself. Genesis. 1. 83. 0Charles Lyell: Principles of Geology. This was the. work that . Drastic. changes, albeit not as all embracing as those envisioned by. There have been. significant changes in state due to such factors as. William Buckland: Geology and Mineralogy considered with. Theology. By 1. 83. Buckland had. abandoned the Noachian flood as a source of major. Instead he postulated numerous. Jean Baptiste de Beaumont: Notice sur des Systemes de Montagnes. He argued. that as the Earth cools its volume slowly reduces. The. shrinkage causes the formation of mountains via. Hugh Miller: The Testimony of the Rocks. Miller was. a very popular creationist geologist. He believed that the. Noachian flood was a local flood in the Mideast and did not. Earth was young. On page 3. Chamberlain (a. geologist). All of them challenged the likelihood of. Kelvin's assumptions. Radiometric Dating. Science. in Christian Perspective. Radiometric. Christian Perspective. Dr. Wiens. 94. 1 Estates Drive,Los Alamos, NM 8. RCWiens@MSN. Com. Wiens has a Ph. D in Physics, with a minor. Geology. His Ph. D thesis was on isotope ratios in meteorites, including. He was employed at Caltech's Division of Geological. Planetary Sciences at the time of writing the first edition. He is. presently employed in the Space & Atmospheric Sciences Group at the Los. Alamos National Laboratory. First edition 1. 99. Radiometric dating- -the process of determining the age. There are over forty such techniques, each using. It has. become increasingly clear that these radiometric dating techniques agree with. Earth was. created a very long time ago. Further evidence comes from the complete. Many Christians have been led to. Many. are also unaware that Bible- believing Christians are among those actively. This. paper describes in relatively simple terms how a number of the dating techniques. In the. process the paper refutes a number of misconceptions prevalent among Christians. This paper is available on the web via the American Scientific. Affiliation and related sites to promote greater understanding and wisdom on. Christian community. TABLE OF CONTENTSIntroduction. Overview. The Radiometric Clocks. Examples of Dating Methods for Igneous Rocks. Potassium- Argon. Argon- Argon. Rubidium- Strontium. Samarium- Neodymium, Lutetium- Hafnium, and Rhenium- Osmium. Uranium- Lead. The Age of the Earth. Extinct Radionuclides: The Hourglasses that Ran Out. Cosmogenic Radionuclides: Carbon- 1. Beryllium- 1. 0, Chlorine- 3. Radiometric Dating of Geologically Young Samples. Non- Radiogenic Dating Methods for the Past 1. Years. Ice Cores. Varves. Other Annual- Layering Methods. Thermoluminescence. Electron Spin Resonance. Cosmic Ray Exposure Dating. Can We Really Believe the Dating Systems? Doubters Still Try. Apparent Age? Rightly Handling the Word of Truth. Appendix: Common Misconceptions Regarding Radiometric Dating. Techniques. Resources on the Web. Further Reading: Books. Acknowledgements. More About the Author Glossary. Introduction. Arguments over the age of the Earth have sometimes been. Bible as God's word. Even though the. Earth's age is never mentioned in the Bible, it is an issue because those who. Genesis can calculate an. Assuming a strictly literal interpretation of the. Earth would be less than ten thousand years old. Radiometric. dating techniques indicate that the Earth is thousands of times older than. Many Christians accept. Genesis account in less scientifically literal ways. Unfortunately, much of the literature available to Christians has been. The next few pages cover a broad overview of radiometric. The goal is to promote greater. Christian community. Many. people have been led to be skeptical of dating without knowing much about it. God has called us to be . In spite of this, differences still occur within the. A disagreement over the age of the Earth is relatively minor in the. Christianity; it is more important to agree on the Rock of Ages. But because God has also called us to wisdom, this. Overview. Rocks are made up of many individual crystals, and each. Most of the elements in nature are stable and. However, some elements are not completely stable in their natural. Some of the atoms eventually change from one element to another by a. If there are a lot of atoms of the original. The passage of time can be charted. Radiometric dating can be compared to an hourglass. When the. glass is turned over, sand runs from the top to the bottom. Radioactive atoms. You cannot predict exactly when. Once all of the. sand has fallen out of the top, the hourglass will no longer keep time unless it. Similarly, when all the atoms of the radioactive element. Figure 1. The rate of loss of sand from from the. In exponential decay the amount of material decreases by half during. After. two half- lives one- fourth remains, after three half- lives, one- eighth. If it takes a certain. In the next. interval, with only a fourth remaining, only one eighth of the original total. By the time. ten of these intervals, or half- lives, has passed, less than one thousandth of. The. equation for the fraction of parent atoms left is very simple. No deviations. have yet been found from this equation for radioactive decay. Also unlike the hourglass, there is no way to change the rate. If. you shake the hourglass, twirl it, or put it in a rapidly accelerating vehicle. But. the radioactive atoms used in dating techniques have been subjected to heat. Earth or other planets without any significant change in their. If it. has a hole allowing the sand grains to escape out the side instead of going. Similarly. a rock that is to be dated must be sealed against loss or addition of either the. If. it has lost some of the daughter element, it will give an inaccurately young age. For. igneous rocks the event is usually its cooling and hardening from magma or lava. For example carbon has isotopes of weight. C, 1. 3C, 1. 4C). Some Naturally Occurring Radioactive. Isotopes and their half- lives. Radioactive Isotope(Parent)Product(Daughter)Half- Life(Years)Samarium- 1. Neodymium- 1. 43. Rubidium- 8. 7Strontium- 8. Rhenium- 1. 87. Osmium- 1. Lutetium- 1. 76. Hafnium- 1. Thorium- 2. 32. Lead- 2. Uranium- 2. 38. Lead- 2. Potassium- 4. 0Argon- 4. Uranium- 2. 35. Lead- 2. Beryllium- 1. 0Boron- 1. Chlorine- 3. 6Argon- 3. Carbon- 1. 4Nitrogen- 1. Uranium- 2. 34. Thorium- 2. Thorium- 2. 30. Radium- 2. Most half- lives taken from Holden, N. E. 6. 2, 9. 41- 9. Isotopes with. relatively short half- lives are useful for dating correspondingly shorter. Work. on radiometric dating first started shortly after the turn of the 2. However. by now we have had over fifty years to measure and re- measure the half- lives for. Very. precise counting of the decay events or the daughter atoms can be done, so while. For example. recall that only one gram of material contains over 1. Even if only one trillionth of the atoms decay in one year. The uncertainties on the half- lives given in the table are. All of the half- lives are known to better than about two percent. There is no evidence. In fact, as discussed below, they. Dating Methods for Igneous Rocks. Now let's look at how the actual dating methods work. Igneous. rocks are good candidates for dating. Recall that for igneous rocks the event. When the molten. material cools and hardens, the atoms are no longer free to move about. Daughter. atoms that result from radioactive decays occurring after the rock cools are. These atoms are like. Determining the age. First one needs to measure the number of. Then the half- life is used to calculate the time it took to. However, there is one complication. One cannot always assume. It turns out that there are. But in most cases. Most. of the time one can use the different amounts of parent and daughter present in. Each dating mechanism deals with this problem in its own way. Some. types of dating work better in some rocks; others are better in other rocks. Let's examine some of the. Potassium- Argon. Potassium. is an abundant element in the Earth's crust. One isotope, potassium- 4. This is not a problem because. It. is possible to date some rocks by the potassium- calcium method, but this is not. Argon, on the other hand, is a gas. Whenever rock is. Once the. molten material hardens, it begins to trap the new argon produced since the. In this way the potassium- argon clock is clearly. In its simplest form, the geologist simply needs to measure. The. age is given by a relatively simple equation: t = h x ln. This is usually trapped in the form. One percent of the air we breathe. Any extra argon from air bubbles may need to be taken into. This would most likely be the. One must have a. way to determine how much air- argon is in the rock. This is rather easily. The ratio of argon- 4. Thus, if one measures argon- 3. One of the best ways of showing that an age- date is correct. Some. young- Earth proponents recently reported that rocks were dated by the. But the potassium- argon method, with its. The. false radiometric ages of several million years are due to parentless. Note that it would be extremely unlikely for another. Getting agreement between. Although. potassium- argon is one of the simplest dating methods, there are still some. When this does happen. This gas can have a higher. This. is called parentless argon- 4. In these slightly unusual. However. scientists in the mid- 1. Argon- Argon. Even though it. This method uses exactly. In. effect, it is a different way of telling time from the same clock. Instead. of simply comparing the total potassium with the non- air argon in the rock, this. In the argon- argon method the rock is placed near the center. A nuclear reactor emits a. Argon- 3. 9 is not found in nature because. The rock is then heated in a furnace to release both. The. heating is done at incrementally higher temperatures and at each step the ratio. If the argon- 4. 0 is from decay of. On the. other hand, if there is some excess argon- 4. Figure 2 is an example of a good argon- argon date. When. this is done, the plateau in the figure represents an age date based on the. There are occasions when the argon- argon dating method does. This. most often occurs if the rock experienced a high temperature (usually a thousand. Fahrenheit or more) at some point since its formation. An. example of an argon- argon analysis that did not yield an age date is shown in. Figure 3. Notice. This. is also true of a number of other igneous rock dating methods, as we will. Figure 3. Rubidium- Strontium. In. nearly all of the dating methods, except potassium- argon and the associated. Using these methods is a little like trying to. One can think of ways to correct for this in an. One could make a mark on the outside of the glass where the sand. Or if one is clever she or he could examine the. By knowing how long it takes all of the sand to fall, one. Similarly, there are good. Strontium has several other. The ratio of strontium- 8. But when the rock first cools, all parts of.
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