STUDY OF HEATING HISTORY IN ARCHAEOLOGICAL MATERIALS -COOKING EVIDENCE, AFFECTED VOLCANIC DISASTER, ETC.

我们研究了考古遗迹和/或考古样品中的剩磁磁化的加热特性，以阐明它们的加热历史。为此，尝试开发新的实验方法。由修正的Thellier方法和精确的热退磁等组成的方法利用了加热样品的热释磁特性。在日本，有几处受火山灾害影响的考古遗址，其中火山沉积物受到的热影响是重要的信息。在古冢时期被春名山的沉积物完全破坏的群马县Komochi村遗址，我们通过开发的方法研究了浮石和火山碎屑流在超过300 ℃的高温下达到的情况，这支持了考古学上提出的证据。利用考古地磁测年法确定了这次火山灾害发生的年代为6世纪中期，这与考古学研究结果相一致。对多伊坦-巴尔加斯遗址蒙古乌戈代宫（13世纪）使用的瓦片进行了测年，发现了二次加热的迹象。从磁化方向看，该瓦片曾用于建造宫殿的天花板。Thellier方法估计的150 ℃的加热温度表明宫殿的火灾可能与战争破坏有关。该方法也成功地应用于其他考古样品的再加热证据及其年龄的调查。由此可见，利用磁性研究创新的加热参数（温度）成为考古学中重要而有用的信息。

We studied the heating properties of remanent magnetization in archaeological remains and/or archaeological samples to elucidate their heating histories. For this purpose, development of new experimental method was attempted. The method composed of the revised Thellier's method and the precise thermal demagnetization etc. utilizes the special qualities of thermoremanent magnetization in the heated samples.In Japan, there are several archaeological ruins affected by volcanic disaster, where the heating influence subjected by the volcanic deposits is the important information. At the ruin of Komochi-village in Gumma Prefecture completely damaged by the deposits from Mt.Haruna at the perid of ancient burial mounds, we studied through the developed method that the pumice-fall and the pyroclastic flow have reached at high temperature over 300 ℃, which supports the archaeologically suggested evidence. Also, the age of this volcanic disaster is determined by archaeomagnetic dating as the middle 6th century, which is concordant with the archaeological study.When the method was applied on the tiles used at the Mongolian Ogodai Palace (13th century) of Doityn-Balgas ruin, the sign of secondary heating was found. The direction of remanent magnetization suggests that the the has been used to construct the ceiling of the Palace. The estimated heated temperature of 150 ℃ studied by the Thellier's method indicates that the firing of the Palace may have occurred related with the war damage.The methods were also successfully applied on the other archaeological samples to investigate the reheated evidence and its age. We conclude that the heating parameter (temperature) innovated using the magnetic study becomes the important and useful information in archaeology.