研究の全体像

 　13世紀代のモンゴル帝国が世界史に与えた影響は「モンゴル・インパクト」と呼ばれています。その中でも、日本への襲来とその終焉の地である鷹島海底遺跡は極めて特異な存在です。1281年、日本制圧を目指し、兵員約14万人を乗せた総数4,400艘の元軍船団は、長崎・佐賀県境にある伊万里湾の湾口に位置する鷹島の周辺海域において、暴風雨に見舞われ、その多くが海底に沈んだと伝えられています。

　本研究では、伊万里湾に沈んだ元軍の沈没船および関連遺物を対象とし、日本へのモンゴル襲来の実態を解明するとともに、日本の水中考古学研究と水中文化遺産保護行政の推進を図る中で若手研究者の育成を行い、独自の学会設立を目指します。さらに「モンゴルインパクト」の重要な証拠である海底から検出したモンゴル襲来関連遺物の保存・活用手法を検討するための世界史的視野に立った国際的共同研究を行なうとともに、日本で開発した水中文化遺産の保護・活用手法について、さまざまに異なる環境に対応できる安全・安価な手法として、世界各国への技術移転を図ることによって、世界の海底遺跡出土遺物に対する保存活用手法研究をリードします。

Overview of the Research

Among the impacts of the thirteenth-century Mongol Empire on world history, collectively referred to as the “Mongol Impact,” the Mongol invasions of Japan and the Takashima Underwater Site, where these invasions came to an end, represent an exceptionally unique historical phenomenon. In 1281, the Mongol fleet, consisting of approximately 4,400 vessels carrying about 140,000 troops for the purpose of conquering Japan, is said to have been struck by a violent storm in the waters surrounding Takashima Island, located at the entrance to Imari Bay on the border between Nagasaki and Saga Prefectures, and that most of the vessels subsequently sank to the seabed.

This project focuses on the shipwrecks of the Mongol fleet and related artifacts lying on the seabed of Imari Bay. It aims to clarify the historical reality of the Mongol invasions of Japan, while promoting underwater archaeological research and the administration of underwater cultural heritage protection in Japan. At the same time, the project seeks to foster young researchers and establish an independent academic society dedicated to this field. Furthermore, while promoting the conservation and utilization of artifacts related to the Mongol invasions recovered from the seabed, which constitute important evidence of the “Mongol Impact,” the project will conduct international collaborative research from the perspective of world history. At the same time, it will promote the international transfer of methods for the protection and utilization of underwater cultural heritage developed in Japan as safe and cost-effective approaches that can be adapted to a wide variety of environmental conditions. Through these efforts, the project aims to lead international research on methods for the conservation and utilization of artifacts recovered from the seabed throughout the world.

研究成果の概要

　本研究では大きく三つの研究成果を目指します。

（1）伊万里湾に残されたモンゴル襲来の実態解明を図ります

　モンゴル襲来の痕跡が埋もれている伊万里湾は東西約13km、南北約8kmの海域です。この海域の中から一定海域を抽出し、ここを対象とした新たな定性、定量的調査研究の実施を図ります。具体的には音波探査装置を用いて海底堆積層情報を取得し、これを解析して海底堆積層中の反応を類型化し、類型ごとに鉄棒による刺突確認調査を実施します。この結果を踏まえて、元軍船をはじめとするモンゴル襲来関係資料が埋もれている可能性が高いと判断した反応について、試掘確認調査を実施します。その上で、試掘確認調査で検出したさまざまな遺物の中から、重要度が高いと判断した資料について引き揚げを行い、保存処理作業を行なった後、公開を図ります。これら一連の調査で獲得した情報を基礎として、伊万里湾全体に広がるモンゴル襲来関連情ついての復元的考察を行います。

（2）日本における水中考古学研究の社会的認知拡大を図り、若手研究者や後継者の育成と水中文化遺産保護・活用の仕組みを作ります

　これまでの鷹島海底遺跡における調査研究成果を踏まえて、新たに水中考古学に携わる人材育成のための教育カリキュラムを構築します。これを全国の大学や研究機関、水中文化遺産を管轄する行政機関に配布し、水中文化遺産研究の周知化、一般化を図ります。その上で、本研究参加者および賛同者が所属する大学や研究機関、行政機関の連携を図るための「水中文化遺産コンソーシアム」を設立します。また、本研究が伊万里湾で実施する現地調査や引き揚げ遺物の保存処理、国際的共同研究やシンポジウムなどの機会を利用して、水中考古学や水中文化遺産に関心をもつ全国の学生および研究機関や行政機関に属する研究者、さらには海外研究者の参加を募ります。

　これらの研究期間中に行う活動実績を踏まえた上で、松浦市や長崎県などの自治体、文化庁などの関係機関と協働し、研究採択期間後も松浦市立水中考古学研究センターを活用した水中文化遺産調査研究手法、および水中文化遺産保護行政に関する研修やトレーニングを継続的に実施する体制を構築します。さらに、これを踏まえて、水中文化遺産の調査研究に関わる探査、三次元計測、保存科学、年代測定、古環境などの文化財科学部門と、水中考古学、歴史学などの研究者が連携する「水中文化遺産学会」（仮称）の創設を図ります。

（3）日本におけるモンゴル襲来研究をアジア各国の歴史研究、さらには水中文化遺産の保護活用に活かします

　本研究の実施については、本研究代表者の仲介によるモンゴル国モンゴル科学アカデミー考古学研究所およびカラコルム国立博物館と、長崎県松浦市立水中考古学研究センターとの間で締結された交流協定に基づき、両機関との共同研究を行うこととなっています。また、現在、韓国国立海洋遺産研究所と松浦市立水中考古学研究センターとの間の交流協定締結の準備も進んでいます。さらに本研究分担者が取り組んでいる海底から出土した遺物の保存処理手法については、鷹島海底遺跡出土資料について取り組んでいる甘味料のトレハロースを用いた保存処理手法について、ヨーロッパやASEAN諸国の水中文化遺産担当者を集めたUNESCO水中文化遺産保護センターでのワークショップの実施や、研究分担者が所属する大学や研究機関での海外研究者の研修受け入れを進めており、国際的研究の進展と技術移転の展開を推進します。

Research Outcomes

This project aims to achieve three major research outcomes.

(1) Clarifying the Historical Reality of the Mongol Invasions Preserved in Imari Bay

Imari Bay, where traces of the Mongol invasions remain buried beneath the seabed, extends approximately 13 km from east to west and 8 km from north to south. A selected area within this bay will be designated for new qualitative and quantitative investigations. Specifically, acoustic survey equipment will be used to obtain information on the seabed sedimentary layers. The acquired data will be analyzed in order to classify anomalies within the sedimentary deposits, and each category of anomaly will subsequently be verified through probing surveys using steel rods. Based on the results of these investigations, test excavations will be carried out at locations where the anomalies are considered to have a high probability of containing remains related to the Mongol invasions, including Mongol warships. Among the artifacts recovered through the test excavations, those judged to be of particular importance will be raised, subjected to conservation treatment, and subsequently made available to the public. Based on the information obtained through this series of investigations, the project will undertake a reconstructive study of the remains related to the Mongol invasions throughout Imari Bay.

(2) Expanding Social Recognition of Underwater Archaeology in Japan and Establishing a Framework for Fostering Young Researchers and Successors and for the Protection and Utilization of Underwater Cultural Heritage

Based on the results of previous investigations at the Takashima Underwater Site, this project will develop an educational curriculum for training personnel who will engage in underwater archaeology. The curriculum will be distributed to universities, research institutions, and governmental agencies responsible for underwater cultural heritage throughout Japan in order to promote wider recognition and general acceptance of this field of research. Furthermore, an Japan Consortium for Underwater Cultural Heritage will be established to promote collaboration among the universities, research institutions, and governmental agencies to which the members and supporters of this project belong. In addition, opportunities provided through the field investigations conducted by this project in Imari Bay, the conservation treatment of recovered artifacts, collaborative research activities, and symposia will be used to encourage the participation of students throughout Japan, as well as researchers affiliated with research institutions and governmental agencies who have an interest in underwater archaeology and underwater cultural heritage.

Based on the achievements of these activities during the research period, this project will collaborate with local governments, including Matsuura City and Nagasaki Prefecture, as well as with relevant organizations such as the Agency for Cultural Affairs, to establish a framework for the continuous implementation of training programs on methods of investigating underwater cultural heritage and on the administration of underwater cultural heritage protection, utilizing the Matsuura City Underwater Archaeology Research Center, even after the completion of the funded research period. Furthermore, based on these achievements, the project will promote the establishment of the Japan Society for Underwater Cultural Heritage (tentative name), which will bring together specialists in cultural heritage science—including underwater survey technology, three-dimensional measurement, conservation science, dating techniques, and paleoenvironmental studies—with researchers in underwater archaeology, history, and related disciplines engaged in the investigation of underwater cultural heritage.

(3) Applying Research on the Mongol Invasions of Japan to Historical Studies in Asian Countries and to the Protection and Utilization of Underwater Cultural Heritage

The implementation of this project is based on an academic exchange agreement concluded between the Institute of Archaeology, Mongolian Academy of Sciences and the Karakorum National Museum, on the one hand, and the Matsuura City Underwater Archaeology Research Center, on the other, through the mediation of the Principal Investigator. Based on this agreement, collaborative research will be conducted between these institutions. In addition, preparations are currently underway for the conclusion of a similar exchange agreement between the National Research Institute of Maritime Cultural Heritage of the Republic of Korea and the Matsuura City Underwater Archaeology Research Center. Furthermore, with regard to conservation methods for artifacts recovered from the seabed, which are being developed by the Co-Investigators of this project, conservation treatments using the naturally occurring sugar trehalose for artifacts excavated from the Takashima Underwater Site are being promoted through workshops at the UNESCO Underwater Cultural Heritage Centre, bringing together specialists responsible for underwater cultural heritage from Europe and ASEAN countries, as well as through the acceptance of overseas researchers for training at the universities and research institutions to which the Co-Investigators belong. Through these activities, the project will promote the advancement of international research and the transfer of technology.