Chapter 3:

Two Worldviews in Conflict
What do thousands of scientists believe about creation and evolution?

Radio Dating

• One need only look in virtually any reference text to quickly find that the earth is thought to be some 4.5 billion years old. As the Encyclopedia Britannica notes, methods such as measuring radioactive decay (radiometric dating) make it possible to estimate the time period when earth’s rocks and associated fossils were formed.^[67]
  
  
• The most commonly used radiometric dating methods are potassium-argon, uranium-lead, and rubidium-strontium. The concept of how these methods work is simple: one element decays into another at a rather predictable rate. Potassium decays and becomes argon. Uranium decays into lead. And rubidium decays into strontium. All three of these decay processes have half-lives measured in billions of years. Half-life is simply the time required for half of the atoms in a pound of uranium, for example, to disintegrate into lead.^[68] That time is approximately 4.5 billion years.
  
  
• The accuracy of these dating methods depends “critically” on several assumptions.^[69] To date a rock by radiometric means, one must first assume:
  
  
  1. What the initial amount of the parent atoms was at the time that the rock formed.
  2. That the original composition of the rock contained no daughter atoms.^[70]
  3. That neither parent nor daughter atoms have ever been added or removed from the rock.
  4. That the decay rate of parent atom to daughter atom has always remained constant.
  
  
• If these assumptions are correct, then the radiometric dates are correct. However, there is no way to independently test these assumptions. If they are wrong, the method could yield faulty dates that might be far too old.
  
  
• To illustrate, suppose there is a burning candle sitting on the table. How long has that candle been burning? This can be calculated if the candle’s burn rate and original length is known. However, if the original length is not known, or if it cannot be verified that the burning rate has been constant, it is impossible to tell for sure how long the candle was burning. A similar problem occurs with radiometric dating of rocks. Since the initial physical state of the rock is unknowable, the age can only be estimated according to certain assumptions.
  
  
• When dating a rock, the geochronologist (scientist who performs the dating procedure) must first assume the rock’s age before it is dated. For example, if a scientist believes a piece of rock is 4.5 billion years old, he or she may then use the uranium-lead dating method because it has a half-life of about 4.5 billion years. This involves circular reasoning, as is clearly evident in the article on dating in the Encyclopedia Britannica: “Most geologists must rely on geochronologists for their results. In turn, the geochronologist relies on the geologist for relative ages.”^[71] The geochronologist must also be sure that the rate of decay, from uranium to lead for example, has remained constant in the rock over the past 4.5 billion years. Furthermore, the amount of uranium in the rock that was present to begin with must also be assumed. And neither uranium nor lead can have ever been added or removed from the specimen by any natural circumstances, catastrophic or otherwise. If all of these assumptions are correct, then the resulting dates are correct. However if even one of these assumptions is wrong, then the resulting dates are erroneous.
  
  
• Why does radiometric dating repeatedly result in very old dates (such as billions of years)? While one explanation is that these dates show the specimens’ true age, another is that one or more of these large assumptions associated with this method of dating is wrong.
  
  
• Scientists have dated lava rock samples from various active volcanoes with the radiometric method. Because the formation of these rocks has recently been observed, radiometric dating should not give them an age of millions of years.^[72] Yet there are many such examples. Consider the following:
  
  
  • Rock which was formed in 1986 from a lava dome at Mount St. Helens volcano was dated by the potassiumargon method as 0.35 ± 0.05 million years old.^[73]
    
    
  • Rocks from five recent lava flows at Mount Ngauruhoe in New Zealand were dated using the potassium-argon method, and resulted in dates ranging from <0.27 to 3.5 million years — but one lava flow occurred in 1949, three in 1954, and one in 1975.^[74]
    
    
  • Salt Lake Crater on Oahu was determined to be 92–147 million years, 140–680 million years, 930–1,580 million years, 1,230–1,960 million years, 1,290–2,050 million years, and 1,360–1,900 years old, using different radiometric dating methods.^[75]
    
    
  • How did 1,000-year-old carbon-dated trees in the Auckland volcanic field of New Zealand get buried under 145,000-465,000 year old potassium-argon-dated lava rock?^[76]
    
    
• One explanation given by scientists for some of these incorrect dates is that excess argon was retained in the rocks when they solidified from a molten state. According to the Canadian Journal of Earth Sciences, “It is common to discard ages which are substantially too high or too low compared with the rest of the group or with other available data such as the geological time scale. . . . The discrepancies between the rejected and the accepted are arbitrarily attributed to excess or loss of argon.”^[77]
  
  
• But if excess argon can cause exaggerated dates for rocks of known age, then why should this dating method be trusted for rocks of unknown age?
  
  
• No one knows for sure if any of the assumptions of radiometric dating are correct, however this is the only method of dating that is considered “absolute.”^[78]Physics professor and researcher Dr. Saami Shaibani, a leading consultant for America’s Federal Bureau of Investigation (FBI), who has 100 scholarly articles to his credit and has been designated “international expert” in his field by the U.S. Departments of Labor and Justice, realizes, “In man-made dating methods, there is assumption upon assumption, plus a couple of more assumptions sprinkled in, plus some blind guesswork. And this masquerades as wonderful, legitimate methodology, but it’s not.”^[79]
  
  
• Creationist scientists distrust the radiometric method of dating, reasoning that 90 percent of the methods that have been used to estimate the age of the earth give far younger ages than those of radiometric dating.^[80] “The age of our globe is presently thought to be some 4.5 billion years, based on [radiometric dating]. Such ‘confirmation’ may be short-lived, as nature is not to be discovered quite so easily. There has been in recent years the horrible realization that radio-decay rates are not as constant as previously thought, nor are they immune to environmental influences. And this could mean that the atomic clocks are reset during some global disaster, and events which brought the Mesozoic [the dinosaur age] to a close may not be 65 million years ago, but rather, within the age and memory of man.”^[81]

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