Dating quartz grains

It is disclosed that the surface morphology of the grains is variable, but quartz grains extracted from one fault gouge sample commonly show a type of texture different from those observed on the grains from the other samples.The surface textures observed under the microscope are tentatively classified into eight types; subconchoidal, orange peel-like, fish scale-like, moss-like, moth-eaten, stalactitic, pot-hole, and coral-like textures. Arranged in the order of their apparent features, it is interpreted that the progressive corrosion of quartz grains by ground water has taken place after faulting.Common silicate minerals like quartz and potassium feldspar contain lattice-charge defects formed during crystallization and from subsequent exposure to ionizing radiation.These charge defects are potential sites of electron storage with a variety of trap-depth energies."Optical dating" typically refers to OSL and IRSL, but not TL.All sediments and soils contain trace amounts of radioactive isotopes of elements such as potassium, uranium, thorium, and rubidium.

Certain materials that are capable of being dated by TL have a mixed history of their quartz content: first, not all quartz grains may have been completely zeroed at the initial instant, and secondly, their geological origin could be varied.

In contrast, Quaternary-inactive faults contain only healed microfracture damage zone.

Cross-cutting relationships between microfractures and a minimum healing temperature of ~100°C suggest that healed microfractures formed before, and at deeper levels, than did unhealed microfractures.

This technique, as thermoluminescence, was originally developed in the 1950s and 1960s to date fired archaeological materials, like ceramics (Aitken, 1985).

Ensuing research in the 1970s documented that marine and other sediments with a prior sunlight exposure of hours to days were suitable for thermoluminescence dating (Wintle and Huntley, 1980).

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