Zircon fission track dating humphreys
The only reliable method for dating kimberlites at present is the lengthy and specialized hydrothermal procedure that extracts 206Pb and 238U from low-uranium zircons. The fission track ages agree well with earlier age estimates.
This paper describes a second successful method by fission track dating of large single-crystal zircons, 1.0-1.5 cm in dimension. Most of the zircons examined in this study are zoned with respect to uranium but linear correlations are established (by regression analysis) between zones of variable uranium content, and within zones of constant uranium content (by analysis of variance).
Uniformitarian scientists assume (1) the initial isotope amounts are known, (2) the decay rate has remained constant at today’s rate, and (3) the sample has remained in a closed system for millions and billions of years.
Evidence is presented that all three assumptions are violated in various contexts, but the RATE project concludes that the assumption of constant decay at today’s rates is the most significant wrong assumption.
Used particularly for edu.au/environment/ee Pages/ee Dating/Quaternary Geochronology/ Trapped Charge Dating PRINCIPAL: energy trapped in crystal imperfections depends on dose rate and time. establish hydration rate for each type of obsidian by examining pieces of known age, or with high pressure and temperature in lab.
Zircon samples from the Cenozoic São Paulo and Taubaté Basins and Mantiqueira Mountain Range (southeast Brazil) were concomitantly dated by zircon Fission Track Method (FTM) and in situ U–Pb dating method.
The results suggest that the São Paulo Basin is composed of sediments from just one source, the Mantiqueira Mountain Range.
On the other hand, the Taubaté Basin presents further sediment sources besides the Mantiqueira Mountain Range.
Besides, it helps me review the results of the RATE project.
C dating, thermoluminescence is related to radioactive decay.
Thermoluminescence is produced by radioactive decay particles (electrons), trapped in mineral grains.
Heating the mineral (or exposure to light) releases electrons, and produces a flash of light, setting the clock to 0 (maybe only partial).
Thereafter, luminescence accumulation is proportional to age.