How Often Do Radioisotope Dating Methods Agree? A Statistical Study of 29,000 Radioisotope Ages in the USGS National Geochronological Database
Type of Submission
Poster
Keywords
Radioisotope Dating, Concordance, Discordance, USGS National Geochronological Database, K-Ar, Rb-Sr, U-Pb, Sm-Nd
Proposal
Radioisotope dating is the cornerstone of the modern geological synthesis, connecting rock layers to concrete numerical ages. However, the numbers sometimes conflict with each other. How often do they conflict? Are there patterns? Several other creationists have performed case studies to answer these questions, but this is the first large-scale statistical study to test whether the patterns they identified hold true across large numbers of rock samples.
We studied the USGS National Geochronological Database, which contains over 29,000 ages from 18,575 rock samples. To perform this analysis, we defined concordance using the error margins in the database. We then adopted two primary strategies: (1) comparing ages that are theoretically equivalent from two different radioisotope methods, and (2) creating a quantitative concordance metric which assigns each sample a score from 0 to 1 by looking at each pair of unique ages from that record. Using this metric, we found the internal concordance of each rock sample and of each radioisotope method.
Our results show a surprisingly small number of ages calculated per rock unit. The majority of samples (74%) were only dated once, and only 34 records had ages from three or more methods. The average concordance score within each method ranged from 0.564 to 0.837. The concordance when comparing two methods was much lower, ranging from 0.000 to 0.794. We observed a general “pecking order” of which methods tend to yield the oldest ages. Our results support what other creationists have found, extending the scope of young-earth radioisotope research to many more rock units.
How Often Do Radioisotope Dating Methods Agree? A Statistical Study of 29,000 Radioisotope Ages in the USGS National Geochronological Database
Radioisotope dating is the cornerstone of the modern geological synthesis, connecting rock layers to concrete numerical ages. However, the numbers sometimes conflict with each other. How often do they conflict? Are there patterns? Several other creationists have performed case studies to answer these questions, but this is the first large-scale statistical study to test whether the patterns they identified hold true across large numbers of rock samples.
We studied the USGS National Geochronological Database, which contains over 29,000 ages from 18,575 rock samples. To perform this analysis, we defined concordance using the error margins in the database. We then adopted two primary strategies: (1) comparing ages that are theoretically equivalent from two different radioisotope methods, and (2) creating a quantitative concordance metric which assigns each sample a score from 0 to 1 by looking at each pair of unique ages from that record. Using this metric, we found the internal concordance of each rock sample and of each radioisotope method.
Our results show a surprisingly small number of ages calculated per rock unit. The majority of samples (74%) were only dated once, and only 34 records had ages from three or more methods. The average concordance score within each method ranged from 0.564 to 0.837. The concordance when comparing two methods was much lower, ranging from 0.000 to 0.794. We observed a general “pecking order” of which methods tend to yield the oldest ages. Our results support what other creationists have found, extending the scope of young-earth radioisotope research to many more rock units.
