this is from an article on my website.
Assumptions, Assumptions…
There are starting assumptions when it comes to solving the age of the earth. The starting assumptions of the old and young earth models actually help determine how data is interpreted. I would be remiss if I didn’t point out that neither model is provable. The creation was not observed and is not testable and really falls outside of the realm of science. What is left then, to try and determine the earth’s age is to make predictions based upon your assumptions and interpret the data to see if it fits your theory. At that point, the data is analyzed.
Let us examine the assumptions that go along with dating processes. Typically, the dating methods are a four step process. First, the rock or system to be dated must be observed in its present state. Second, the rate of a process operating within that system must be measured. These steps are scientific. The third step in the dating method is for a scientist to make assumptions about the past history of the rock or system. Lastly, it is calculated how long the present process would take to produce the present things in that system. The last two steps of the dating method are not scientific. They rely on assumptions to reconstruct the unobserved past. Dating methods are driven by uniformitarianism. This is the belief that there have been no major changes in rates or character of processes that we observe today. In other words, “the present is the key to the past.†Take for example tree ring dating. Though tree ring dating may be fairly accurate, this method still works on uniformitarian assumptions. The actual date of a tree can be different than what the number of rings would lead you to believe. For instance, draught, disease, heat, cold, and wet conditions can effect the formation of tree rings.
In radioisotope dating, there are key assumptions used. The first assumption is that there has always been a constant rate of decay. The second assumption is that there has been no loss or gain to the parent or daughter. The third assumption is that there were known amounts of daughter present at the start. Keep in mind that these three assumptions cannot be proven to be realistic assumptions because the distant past was unobserved and we cannot go back in time to verify whether rates and amounts were the same then as today!
There are many examples of radioisotope dating failing when used to date rocks of known age. In Hawaii, Hanalei Volcano is known to have erupted 1800-1801. Rocks were dated and yielded results ranging from 140 million years to 2.96 billion years. Sunset Crater in Arizona erupted roughly 900 years ago. The potassium argon dating method gave results of 210,000 and 230,000 years old. These are only two examples of many that could be given to show the inaccuracy of radioisotope dating. So then there is another assumption, rocks dated at a known age shows that dating doesn’t work, yet rocks dated at unknown ages is assumed to work!
