ESR studies and ESR dating of quartz

In this work we have investigated quartz grains which were extracted from ignimbrites in Kapadokya, using ESR spectroscopy techniques. It was found from the ESR spectra of the natural quartz that Al and Ti centers were responsible for the observed ESR lines. Their calculated g-factors were found to be g1 = 2.07, g2 = 2.01 for the Al center and g = 1.93 for the Ti center. Thermal behavior of these centers were examined by making isothermal and isochronic annealing experiments. It was shown from these experiments that Ti centers were more stable than the Al centers. Signal growth curves due to the γ-irradiation helped us to estimate the ADs (acquired doses) and the ages of the quartz grains. We have determined the age of the quartz grains to be 1.2 Ma with an error factor of 22%, which falls into the Pliocene epoch in the time scale.