KUWABARA Hisao Tenri University, Faculty of Letters, Associate Professor, 文学部, 助教授 (00234633)
EDWARDS Walter Tenri University, Faculty of International Cultural Studies, Professor, 国際文化学部, 教授 (70258185)
NISHIMURA Yasushi Nara National Cultural Properties Research Institute, Excavation Techniques Section, Section Chief, 埋蔵文化財センター発掘技術研究, 室長 (80000488)
Using electric resistivity and radar prospection equipment, experimental research investigations were conducted at a jar burial cemetery in the Yoshinogari site of Saga prefecture, the Himori subterranean chamber grave (vertical shaft) cemetery in Miyazaki prefecture, the Baba subterranean chamber grave (vertical shaft) cemetery in Kagoshima prefecture, the Nagayama subterranean stone-slab chamber grave cemetery in Kagoshima prefecture, Dantoyama mounded tomb in Hyogo prefecture, and the former site of the Kamihirakawa mounded tomb in Shizuoka prefecture.
As a result, it was demonstrated that radar prospection can clearly identify graves which maintain subterranean cavities intact. Also, with close inspection it is possible to detect chambers which have collapsed, and graves made with stone and the filled-in moats of tombs can also be detected with radar. But vertically dug shafts of subterranean chamber graves are sometimes detectable, and sometimes difficult to discern.
vities appear as areas of low resistance in electric resistivity surveys with the twin electrode configuration made to produce vertical profiles, but in surveys made to cover an area in horizontal fashion they cannot be clearly detected. With the dipole-dipole method it is possible to discern subterranean cavities and building stone in vertical profiles, but attempts at horizontal surveys are few in number and no clear verdict is possible. Continued research in this area is planned for the future.
In conclusion, by using antennae of various frequencies, and setting the survey interval to as small a distance as possible, and moreover by making repeated surveys in which the climatic conditions are taken into consideration, it is possible to obtain more reliable data. Further, it is possible to detect a feature with greater certainty by using resistivity survey in parallel. The above points clearly hold for uniform accumulations such as volcanic ash soil layers, and to a certain extent may apply to clayey soils as well. But conclusions based on only one type of equipment, and from a single survey, should be made with great caution. Less