Radiogenic dating methods
They document twenty-two examples of false rubidium-strontium isochrons and propose that such characteristics are inherited from the molten material's source at great depth in the earth. The straight line plot is again explained by geologic process, not by time-dependent nuclear decay within the rock. Geologists, understandably, have accepted the Rb-Sr "Isochron date" for the Cardenas Lavas and attribute the younger K-Ar "model dates" to be errors caused by uniform argon loss by these rocks after the lava cooled. The Western Grand Canyon lava flows are among the youngest formations of the Grand Canyon. Mitchell, "Name and Age of the Upper Precambrian Basalts in the Eastern Grand Canyon," Geological Society of America Bulletin, 83 (Jan. Such ages defined by these fines are called "isochrons." An "isochron date," which relies on multiple rock samples, is considered to be much more reliable than a "model date" determined from a single rock sample. Isochron confidence is well founded, for the assumptions of the dating method appear to be internally verified. Possible other sources of correlation Anomalies of radiometric dating Why a low anomaly percentage is meaningless The biostrategraphic limits issue Preponderance of K-Ar dating Excuses for anomalies Need for a double-blind test Possible changes in the decay rate Isochrons Atlantic sea floor dating Dating Meteorites Conclusion Gentry's radiohaloes in coalified wood Carbon 14 dating Tree ring chronologies Coral dating Varves Growth of coral reefs Evidence for catastrophe in the geologic column Rates of erosion Reliability of creationist sources Radiometric dating methods estimate the age of rocks using calculations based on the decay rates of radioactive elements such as uranium, strontium, and potassium.On the surface, radiometric dating methods appear to give powerful support to the statement that life has existed on the earth for hundreds of millions, even billions, of years.
That is a good question, which ordinarily requires a lengthy and technical answer.
They have been assigned to the Precambrian strata of the Unkar Group, which contains the lowest and hence oldest strata of the Grand Canyon.
Three whole rock K-Ar dates by Mc Kee and Noble Figure 2. Dutton, "The Tertiary History of the Grand Canyon Disctict," US.
Fictitious Isochron Ages The isochron method assumes that the datable lava flow cooled from molten rock having different Rb/Sr ratios but having uniform mixing isotopically (all samples having the same Sr graph with the slope of the line having no identifiable time significance! Noble, "Age of the Cardenas Lavas, Grand Canyon, Arizona," Geological Society of America Bulletin, 87 (Aug.
Such two-component mixing diagrams produce what Faure calls "fictitious isochrons." Another geologic cause for these straight line plots is offered by Brooks, James, and Hart.