Optical dating techniques

Chapter 1: Introduction Chapter 2 2.1: Natural radioactivity 2.2: The natural dose-rate 2.3: Evaluation of dose-rate 2.4: Artificial irradiation 2.5: Dependence on rate at which dose is delivered, and on temperature Chapter 3 3.1: Sample collection 3.2: Preparation of aliquots for OSL measurement 3.3: Measurement of OSL Chapter 4 4.1: Unwanted signals: backgrounds and residuals 4.2: Irradiation and preheating 4.3: Multi-aliquot methods 4.4: The single-aliquot Chapter 5 5.1: Aeolian deposits 5.2: Water-laid sediment 5.3: Organic-rich sediment 5.4: Glaciation-related deposits 5.5: Earthquake-related studies 5.6: Two unusual applications 5.7: Applications other than sediment dating Chapter 6 6.1: Factors affecting rapidity of bleaching 6.2: The level reached 6.3: Intrinsic indications about zeroing - analysis of the shine-down curve 6.4: Other intrinsic indications about zeroing Chapter 7 7.1: Thermal transfer 7.2: Shine-curve analysis revisited 7.3: Reasons for preheating 7.4: Preheating of feldspars and polymineral fine-grains 7.5: Preheating of quartz 7.6: Quartz preheating and sensitivity change 7.7: Retention lifetimes '...highly timely and very welcome...

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There are advantages and disadvantages to using each.

For quartz one normally uses blue or green excitation and measures the near ultra-violet emission.

Stimulating samples using either blue, green or infrared light causes a luminescence signal to be emitted as the stored unstable electron energy is released, the intensity of which varies depending on the amount of radiation absorbed during burial.

The radiation damage accumulates at a rate over time determined by the amount of radioactive elements in the sample.

The photons of the emitted light must have higher energies than the excitation photons in order to avoid measurement of ordinary photoluminescence.

A sample in which the mineral grains have all been exposed to at least a few seconds of daylight can be said to be of zero age; when excited it will not emit any such photons. The minerals that are measured are usually either quartz or feldspar sand-sized grains, or unseparated silt-sized grains.Written by one of the foremost experts on optical dating, this book aims to bring together in a coherent whole the various strands of research that are ongoing in the area.It gives beginners an introduction to the technique as well as acting as a valuable source of up to date references.The text is divided into three parts; main text, technical notes and appendices.In this way the main text is accessible by those researchers with a limited knowledge of physics, with the technical notes providing depth of understanding for those who require it.Optical dating is a rapidly developing technique, used primarily in the dating of sediments deposited in the last 500,000 or more years.

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