مقایسهٔ روش‌ها

	Argon-Argon Dating	Bayesian Chronological Modeling
حوزه	باستان‌شناسی	باستان‌شناسی
خانواده	Regression model	Regression model
سال پیدایش	1999	2009
پدیدآور	Craig Merrihue and Grenville Turner (method, 1960s); synthesized by McDougall and Harrison	Christopher Bronk Ramsey (OxCal); Caitlin Buck and colleagues (Bayesian framework)
نوع	Radiometric dating clock measuring argon isotope ratios after neutron irradiation	Bayesian statistical model combining dates with prior archaeological information
منبع بنیادین	McDougall, I., & Harrison, T. M. (1999). Geochronology and Thermochronology by the 40Ar/39Ar Method (2nd ed.). Oxford University Press. ISBN: 9780195109207	Bronk Ramsey, C. (2009). Bayesian Analysis of Radiocarbon Dates. Radiocarbon, 51(1), 337-360.
نام‌های دیگر	40Ar/39Ar Dating, Argon-Argon Geochronology, Single-Crystal Laser-Fusion Dating, Ar-Ar Step-Heating Dating	Bayesian Radiocarbon Modeling, OxCal Bayesian Chronology, Bayesian Phase Modeling, Chronological Bayesian Modeling
مرتبط	3	3
خلاصه	Argon-argon (40Ar/39Ar) dating is the modern, high-precision successor to conventional potassium-argon dating, in which the parent potassium is measured indirectly by converting it to a measurable argon isotope inside a nuclear reactor. A potassium-bearing sample is irradiated so that potassium-39 transmutes into argon-39, which then stands as a proxy for the parent potassium; both the radiogenic argon-40 daughter and this argon-39 proxy can be measured on the same aliquot by a single mass spectrometer, eliminating the sample-heterogeneity problem of the older method. Crucially, the gas can be released either by fusing a single crystal with a laser or by heating the sample in incremental steps, the latter producing an age spectrum that reveals argon loss, excess argon, and disturbance. Synthesized in McDougall and Harrison's monograph, the technique delivers the precise, internally checkable ages now standard for dating volcanic deposits at hominin and Palaeolithic sites.	Bayesian chronological modeling refines archaeological chronologies by combining the calibrated probability distributions of individual radiocarbon dates with prior archaeological knowledge — most importantly the stratigraphic order of samples and their grouping into phases — within a single Bayesian model. Rather than treating each date in isolation, the method asks what calendar ages are jointly consistent with all the dates and all the ordering constraints at once, and returns sharpened posterior distributions for each date plus estimates of the start, end, and duration of phases and the timing of events. Formalized by Caitlin Buck and colleagues and made widely usable through Christopher Bronk Ramsey's OxCal software, with the international IntCal calibration curve as input, it has become the standard framework for high-precision archaeological dating.