Radiometric dating proved wrong

The general idea is that many different minerals are formed, which differ from one another in composition, even though they come from the same magma.

radiometric dating proved wrong-66

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, lead), so the higher the ratio of lead to uranium, the older the rock must be.

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.

This calls the whole radiometric dating scheme into serious question.

Evidence of this type led them to look into the possibility that a single magma might produce rocks of varying mineral content. Bowen discovered that as magma cools in the laboratory, certain minerals crystallize first.

A pioneering investigation into the crystallization of magma was carried out by N. At successively lower temperature, other minerals begin to crystallize as shown in Figure 3.6.

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.

On the upper left branch of this reaction series, olivine, the first mineral to form, Ml] react with the remaining melt to become pyroxene.

This reaction will continue until the last mineral in the series, biotite mica, is formed.

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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