Dating of Gediz delta deposits by electron spin resonance (ESR) techniques

In this work, Elektron Spin Rezonans (ESR) technique was used to date called bivalves, gastropods, ostrokod and echinic shells that are collected from around the Gediz Delta. Shell samples used in this study, are taken from (8-9), (10-11), (24-25) and (25-26) m. To examine and determine thermal life and charactersitics of free radicals created by ESR signals of 400Gy irradiated and natural (non-irradiated) the shell samples were annealed isochronally and kinetic. Then, for each sample the ESR signal intensity were measured and dose-response curves were constructed depending on increasing dose of gamma radiation. The thermal stability and dose response of the ESR signals were found to be suitable for an age determination using a signal. The ESR signal growth curve on additional γ-irradiation for samples collected from (8-9) meter depths has been best fitted by of one exponential saturation function. Collected from (10-11), (24-25) and (25-26) m depths has been best fitted by lineer function. Geological dose values were determined by extrapolation of these curves. To determine concentrations of radioactiveelements 238U, 232Th and 40K in the shells and surrounding sediments were measured by Inductively Coupled Plasma- Mass Spectrometer (ICP-MS) analysis. In the final part of the study, geological formation age of the sample was calculated by using determined geological dose and 238U, 232Th and 40K data on ROSY software.