In all other cases, the error propagation uses a first order Taylor approximation: ].It is generally quite straightforward to obtain the isotopic ratio estimates and their uncertainties using most data acquisition software.
For synchronously acquired isotopic data, such as Ar-data measured by noble gas mass spectrometry or U-Pb data measured by laser ablation inductively coupled mass spectrometry (LAICPMS), this is achieved using redundant ratios.For example, in the case of ]) are based on the same number of data points.Overdispersed datasets require further processing with continuous or discrete mixture models that are discussed in Section 9.Sections 10-15 provide specific details about the Rb-Sr, Sm-Nd, Lu-Hf, Re-Os, Ar, U-Pb, Pb-Pb, U-Th-He, fission track and U-series dating methods.The principal aim of this paper is to provide a general overview of the design philosophy and basic operating principles behind the software, rather than a detailed manual of all its components.
Section 2 discusses the software architecture, which uses a modular design with future-proofness and extendability in mind.
Section 16 introduces a selection of statistical methods to help interpret collections of multiple geochronological datasets that are useful in detrital geochronology.
Finally, Section 17 sets out a roadmap for future developments to improve the accuracy and precision of geochronological data, and to provide closer integration of website is perfectly platform-independent.
Section 6 introduces a weighted mean plot to visualise multiple age estimates and proposes a heuristic method to detect outliers.
Section 7 presents three approaches to construct confidence intervals for isochron ages, weighted means and so forth.
The computer code for both programs is made available under the GPL license, which permits re-use and modification provided that any derived code is released under the same conditions (Free Software Foundation, 2007). Without analytical uncertainties, it is impossible to ascertain whether the difference between two geochronological dates is real, or simply an artifact of analytical imprecision.