ブックタイトルRILAS 早稲田大学総合人文科学研究センター研究誌

概要

RILAS 早稲田大学総合人文科学研究センター研究誌

WASEDA RILAS JOURNALデジタルNO. 3技(2015.術・非10)破壊的手法を用いた古代寺院における伽藍配置の調査研究デジタル技術・非破壊的手法を用いた古代寺院における伽藍配置の調査研究──下総龍角寺の測量・GPR(レーダー探査)調査──城倉正祥・ナワビ矢麻Research on the Placement of Buildings in an Ancient Temple Using Digital andNon-Destructive Techniques:Mesurement Survey and GPR at Simousa Ryukakuji TempleMasayoshi JOKURA・Yama NAWABIAbstractRyukakuji Temple (Chiba Prefecture, Inba-gun, Sakae-machi) is the oldest temple in the eastern part ofJapan that dates from ancient times. While it has been under investigation since the 1940s, there are stillmany unclear points to it. The biggest problem is that the topographical information for the area is old, and ananalysis based on accurate terrain information has not been performed.This survey was conducted so as to clarify the placement of the founding period temple and to reveal theevolution of the ruins from ancient to modern times. In order to accomplish these tasks, we performed a topographicalsurvey and a GPR (ground penetrating radar) survey.For the topographical survey, we adopted a direct method and created a survey map of 10cm contours usinglevels and total stations. As a result, the north side of the terrain became clearly visible. In addition to discerningthe foundation of the main hall and tower, we revealed the possibility the northwest corner reflectsthe position of the corridor of the founding period.GPR is a geophysical survey method aimed at understanding the position and shape of remains in a nondestructiveway. In this survey, we obtained a reaction for the foundations of the main hall, the tower, and thenorthwest side of the corridor. On the other hand, since we could not confirm reaction at the existing Niohmonarea: It was found to be a gate that was built some time after the early modern period. The GPR resultsabove are consistent with the outcome of the topographical survey, and therefore it is possible to estimate theoriginal placement of the temple.From the overall results of the survey, we can assume a different placement of the temple building fromthat of previous research. In addition, we have gained a deeper understanding of the transformation process ofthe axis of the precincts of the ruins. Based on these results, we need to continue to re-organize past researchresults, promote new excavation efforts, and discuss the placement and subsequent transition of the templebuildings of Ryukakuji.はじめに千葉県印旛郡栄町に所在する天竺山寂光院龍角寺は、白鳳期に創建された房総を代表する古刹である。本尊の薬師如来坐像の頭部は旧山田寺講堂本尊と通じる作風として知られ、国の重要文化財に指定されている。また、出土した古瓦も山田寺系の単弁蓮華文軒丸瓦と重弧文軒平瓦で、飛鳥の王権との深い関係性の中で創建された点が指摘される。瓦に関しては、龍角寺瓦窯・五斗蒔瓦窯の発掘とその出土品の研究が進み、特に文字瓦の分析が成果を上げている。一方、遺構に関しては、1948年以降に継続385