Scientific proof against carbon dating Sexy cam to cam nigeran
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.
Radiometric dating is largely done on rock that has formed from solidified lava.
Oftentimes the rate of cooling occurs rapidly enough to prohibit the complete transformation of calcium-rich feldspar into sodium-rich feldspar.
In these instances, the feldspar crystals will have calcium-rich interiors surrounded by zones that are progressively richer in sodium.
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.