rules of dating my teenage daughter - How accurate is radioactive isotope dating

Geologists assert that 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.But even if it is true that older radiometric dates are found lower down in the geologic column, which is open to question, this can potentially be explained by processes occurring in magma chambers which cause the lava erupting earlier to appear older than the lava erupting later.Such processes can cause the daughter product to be enriched relative to the parent, which would make the rock look older, or cause the parent to be enriched relative to the daughter, which would make the rock look younger.

how accurate is radioactive isotope dating-85

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.

Most scientists today believe that life has existed on the earth for billions of years.

This belief in long ages for the earth and the existence of life is derived largely from radiometric dating.

Such a large variety of igneous rocks exists that it is logical to assume an equally large variety of magmas must also exist.

However, geologists have found that various eruptive stages of the same volcano often extrude lavas exhibiting somewhat different mineral compositions, particularly if an extensive period of time separated the eruptions.But at the same time, it will be enriched in the elements contained in the later forming minerals, namely sodium and potassium.Further, the silicon content of the melt becomes enriched toward the latter stages of crystallization.As the crystallization process continues, the composition of the melt (liquid portion of a magma, excluding any solid material continually changes.For example, at the stage when about 50 percent of the magma has solidified, the melt will be greatly depleted in iron, magnesium, and calcium, because these elements are found in the earliest formed minerals.Of course, there are many problems with such dating methods, such as parent or daughter substances entering or leaving the rock, as well as daughter product being present at the beginning.

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