The Age measurement of the tephra layers, fill in the San in district since the middle Pleistocene. Using the Thermo luminescence technique

本文首先研究了几种条件下热释光辐射电荷的积累速率。结果表明，厚度为10cm的铅盒内没有发生辐射电荷积累。黄铜管或铜管中的额外辐射电荷没有发生。结果表明，埋在地下的热释光元件在不同区域的辐射电荷不同。因此，很明显，辐射电荷率必须在取样的同一点测量。笔者对三音地区火山玻璃的折射率、矿物组成等进行了考察。并对分布在北陆地区的部分麻风标本进行了检测，作为参考。并测量了这些材料的热释光强度。结果表明，该方法可以应用于所有这些领域。然而，由于某些物质的矿物组成，辐射电荷积累很少。例如，含有大量石英粒子的K-Tz具有较大的辐射电荷积累。另一方面，Oginsen地区的热释光强度较弱，其地层年龄比K-Tz早。与K-Tz相比，北陆地区较古老的火山碎屑流沉积层的热释光较强。大森沉降浮石的热释光强度存在明显差异。热释光强度可以用其沉降年龄来计算。

At first, the accumulation rate of radiation charge of thermoluminescence in several conditions are studied in this research. As the results, accumulation of radiation charge weren't occur in the lead box of the thickness 10cm. The additional radiation charge in the brass or copper tubes did not occur. It is revealed that the radiation charge of the thermoluminescence elements laid under the ground were different at each region. So, it is clear that the radiation charge rate must be measured at the same point where tephra were sampled.In San'in district, the author examined the tephra layers as to refractive index of volcanic glass, mineral composition and a so on. And as a reference, some samples of tephra distributed in Hokuriku district were examined. And also, the thermoluminescence intensity of these tephra were measured. It is revealed that this technique is able to apply for all of these tephra. However, the radiation charge accumulation is a very few in some tephra because of their mineral composition. For example, K-Tz, which contains large quantities of quartz particle, has large radiation charge accumulation. On the other hand, the tephra of Oginsen area, which are older than K-Tz as to stratigraphically, their thermoluminescence intensity are weak. And the thermoluminescence of the quite older pyroclastic flow deposits of Hokuriku is quite strong in comparison with the K-Tz. Daisen fallout pumices have a clear deference thermoluminescence intensity each other. The thermoluminescence intensity of tephra can be calculated into their fallout age.