Index fossil dating evolution

Is There Circular Logic in Fossil Dating? | secularmoralatheist

index fossil dating evolution

Paleontology seeks to map out how life evolved across geologic time. Misleading results can occur if the index fossils are incorrectly dated. Prior to radiometric dating, evolution scientists used index fossils a.k.a. relative dating to ascertain the age of their discoveries. A paleontologist would take the. Using relative and radiometric dating methods, geologists are able to answer the scientists know that living primates evolved from fossil primates and that this . Usually index fossils are fossil organisms that are common, easily identified.

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If it sounds like circular reasoning, it is because this process in reality is based upon circular reasoning. Henry Morris as follows: These long time periods are computed by measuring the ratio of daughter to parent substance in a rock, and inferring an age based on this ratio. This age is computed under the assumption that the parent substance say, uranium gradually decays to the daughter substance say, leadso the higher the ratio of lead to uranium, the older the rock must be.

While there are many problems with such dating methods, such as parent or daughter substances entering or leaving the rock, e. Geologists assert that generally speaking, older dates are found deeper down in the geologic column, which they take as evidence that radiometric dating is giving true ages, since it is apparent that rocks that are deeper must be older.

Dating Fossils – How Are Fossils Dated? - sendangsono.info

But even if it is true that older radiometric dates are found lower down in the geologic column which is open to questionthis can potentially be explained by processes occurring in magma chambers which cause the lava erupting earlier to appear older than the lava erupting later.

Lava erupting earlier would come from the top of the magma chamber, and lava erupting later would come from lower down. A number of processes could cause the parent substance to be depleted at the top of the magma chamber, or the daughter product to be enriched, both of which would cause the lava erupting earlier to appear very old according to radiometric dating, and lava erupting later to appear younger.

index fossil dating evolution

Other possible confounding variables are the mechanisms that can alter daughter-to-parent ratios. We can see that many varieties of minerals are produced from the same magma by the different processes of crystallization, and these different minerals may have very different compositions.

It is possible that the ratio of daughter to parent substances for radiometric dating could differ in the different minerals.

Clearly, it is important to have a good understanding of these processes in order to evaluate the reliability of radiometric dating.

Other confounding factors such as contamination and fractionation issues are frankly acknowledged by the geologic community, but are not taken into consideration when the accuracy and validity of these dating methods are examined.

The following quotation from Elaine G. Kennedy addresses this problem. Contamination and fractionation issues are frankly acknowledged by the geologic community. For example, if a magma chamber does not have homogeneously mixed isotopes, lighter daughter products could accumulate in the upper portion of the chamber. If this occurs, initial volcanic eruptions would have a preponderance of daughter products relative to the parent isotopes.

Such a distribution would give the appearance of age. As the magma chamber is depleted in daughter products, subsequent lava flows and ash beds would have younger dates. It does suggest at least one aspect of the problem that could be researched more thoroughly.

The problems inherent in radiometric dating often cause them to be so unreliable that they contradict one another rather than validating each other. It would really be nice if geologists would just do a double blind study sometime to find out what the distributions of the ages are. In practice, geologists carefully select what rocks they will date, and have many explanations for discordant dates, so it's not clear how such a study could be done, but it might be a good project for creationists.

There is also evidence that many anomalies are never reported. Since the rock formation contains both types of fossils the ago of the rock formation must be in the overlapping date range of to million years.

Studying the layers of rock or strata can also be useful. Layers of rock are deposited sequentially. If a layer of rock containing the fossil is higher up in the sequence that another layer, you know that layer must be younger in age. This can often be complicated by the fact that geological forces can cause faulting and tilting of rocks.

Absolute Dating Absolute dating is used to determine a precise age of a rock or fossil through radiometric dating methods.

The Circularity of Fossil Dating (Index Fossils)

This uses radioactive minerals that occur in rocks and fossils almost like a geological clock. So, often layers of volcanic rocks above and below the layers containing fossils can be dated to provide a date range for the fossil containing rocks. The atoms in some chemical elements have different forms, called isotopes.

These isotopes break down at a constant rate over time through radioactive decay.

Index Fossils for Evolution Refuted by Kent Hovind

By measuring the ratio of the amount of the original parent isotope to the amount of the daughter isotopes that it breaks down into an age can be determined.

Getting back to the quotes from the creation sites, I have provided a more complete quote from J. This quote is found on all the creation websites: The geologist has never bothered to think of a good reply, feeling the explanations are not worth the trouble as long as the work brings results. This is supposed to be hard-headed pragmatism. It can be ignored, as not the proper concern of the public. It can be denied, by calling down the Law of evolution.

index fossil dating evolution

It can be admitted, as a common practice. The time scales of physics and astronomy are obtained by comparing one process with another. They can also be compared with the geologic processes of sedimentation, organic evolution and radioactivity.

Or, it can be avoided, by pragmatic reasoning. The first step is to explain what is done in the field in simple terms that can be tested directly.

index fossil dating evolution