Radiometric Dating is not reliable

http://en.wikipedia.org... Potassium–argon dating or K–Ar dating is a radiometric dating method used in geochronology and archaeology. Assumptions According to McDougall and Harrison (1999, p. 11) the following assumptions must be true for computed dates to be accepted as representing the true age of the rock. The parent nuclide, 40K, decays at a rate independent of its physical state and is not affected by differences in pressure or temperature. This is a well founded major assumption, common to all dating methods based on radioactive decay. Although changes in the electron capture partial decay constant for 40K possibly may occur at high pressures, theoretical calculations indicate that for pressures experienced within a body of the size of the Earth the effects are negligibly small. The 40K/39K ratio in nature is constant so the 40K is rarely measured directly, but is assumed to be 0.0117% of the total potassium. Unless some other process is active at the time of cooling, this is a very good assumption for terrestrial samples. The radiogenic argon measured in a sample was produced by in situ decay of 40K in the interval since the rock crystallized or was recrystallized. Violations of this assumption are not uncommon. Well-known examples of incorporation of extraneous 40Ar include chilled glassy deep-sea basalts that have not completely outgassed preexisting 40Ar*,and the physical contamination of a magma by inclusion of older xenolitic material. The Ar–Ar dating method was developed to measure the presence of extraneous argon. Great care is needed to avoid contamination of samples by absorption of nonradiogenic 40Ar from the atmosphere. The equation may be corrected by subtracting from the 40Armeasured value the amount present in the air where 40Ar is 295.5 times more plentiful than 36Ar. 40Ardecayed = 40Armeasured − 295.5 × 36Armeasured. The sample must have remained a closed system since the event being dated. Thus, there should have been no loss or gain of 40K or 40Ar*, other than by radioactive decay of 40K. Departures from this assumption are quite common, particularly in areas of complex geological history, but such departures can provide useful information that is of value in elucidating thermal histories. A deficiency of 40Arin a sample of a known age can indicate a full or partial melt in the thermal history of the area. Reliability in the dating of a geological feature is increased by sampling disparate areas which have been subjected to slightly different thermal histories. Both flame photometry and mass spectrometry are destructive tests, so particular care is needed to ensure that the aliquots used are truly representative of the sample. Ar–Ar dating is a similar technique which compares isotopic ratios from the same portion of the sample to avoid this problem. http://en.wikipedia.org... assumption |əˈsəm(p) sh ən| noun 1 a thing that is accepted as true or as certain to happen, without proof.ConclusionAs I have shown, in order for the radiometric dates to be reliable it must be ASSumed that "The sample must have remained a closed system since the event being dated."No samples have ever met this criteria and thus radiometric dates are un-reliable on this one point alone. My Dad used to have a saying about ASSuming things...