NUMERICAL SIMULATION OF THERMOLUMINESCENCE QUARTZ PARTICLE

Abstract

One of the widely used methods for studying minerals is the thermoluminescent (TL) method, which is used to date Quaternary sedimentary rocks. Usually, the difficulty in using TL dating is the lack of information about the structure of the mineral used in the experiment. For reliable interpretation of experimental data, the authors applied the digital twin method. In this case, all stages of the transformation of the mineral used are modeled from its burial in sedimentary rocks to the stimulation of the TL-signal splash in it under laboratory conditions on special installations, taking into account the unevenness heat transfer inside the sample of this mineral. The paper presents the results of numerical simulation of the TL signal from a spherical particle of natural quartz. The modeling was carried out in two stages. At the first stage, the influence of the burial time of quartz in the sedimentary rocks on its TL signal was determined. For this, the problem was posed of the accumulation of the crystal lattice quartz, information about the time of its presence in the natural radiation field. At the second stage, the TL signal from a spherical particle was simulated, which was heated in an experimental setup from the surface according to a linear law. It was found that, firstly, the burial time of quartz affects the shape of the TL-curve and, therefore, the mineral is applicable for dating. Secondly, it is necessary to control the heating mode of the quartz sample, since at high heating rates, heat transfer irregularities are significant for particles with a large radius. It also affects the shape of the TL signal and, as a result, can make it difficult to obtain age definitions or distort them. To assess the effect of non-uniformity of heat transfer, a dimensionless similarity parameter was proposed, which connects the radius of the particles and the heating rate.