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Research paper−84−Synthesiology - English edition Vol.2 No.2 pp.84-94 (Oct. 2009) Specifically, I focused on the traces of earthquakes found during the archaeological excavations. In this paper, I shall describe the process of research and outline the results.2 History of research of active faultsIn Japan, research on active faults as cause of inland earthquakes started in the 1960s. I started studying active faults using geomorphological and geological methods from the early 1970s, mainly in the Kansai region. At the time, few active faults were known, and it was an “age of reconnaissance and discovery of active faults” where new faults were identified and their basic attributes were surveyed.In 1976, about 30 active fault researchers organized the Research Group for Active Faults. The objective of this group was to create a general catalog by investigating the characteristics of active faults that are distributed throughout Japan, using a uniform standard. As a member of the research group, I engaged in the survey of faults in Kinki, Chugoku, and Shikoku regions. Using the 1:40,000 aerial photographs, the positions of the faults were estimated from geomorphological viewpoint, and the presence of faults was checked through geological survey. The result was published in 1980[1].I joined the Geological Survey of Japan, Agency of Industrial Science and Technology, Ministry of International Trade and Industry in 1979, when the compilation of the “1:500,000 Neotectonic Maps” started. Japan was divided into 15 regions on 1:500,000 scale maps to which geological information and major faults were added. As part of the neotectonic map series, compiled maps of the 15 regions were published from 1982 to 1987[2].1 IntroductionThe Japanese Archipelago was shaped into its thin, long form as the plates covering the surface of the earth pushed against each other and caused earthquakes. The residents of the Japanese Archipelago have experienced the devastation of earthquakes, and continue to be exposed to their threat. Recently, the Iwate Miyagi Inland Earthquake occurred on June 14, 2008, and the Great Hanshin Awaji Earthquake (official name designated by the Japan Meteorological Agency is “1995 Southern Hyogo Prefecture Earthquake”) on January 17, 1995 claimed the lives of 6,434 people. In the near future, epicenetral earthquake is expected to hit the Tokyo area, and mega-earthquakes such as the Tokai, Tonankai, and Nankai earthquakes are expected to occur during this century in the Pacific region from Kanto to Kyushu.In Japan, which is one of the most earthquake-prone countries in the world, measures against earthquakes are mandatory, and researches on predictions of place, magnitude, and time of earthquakes, as well as projections of damages and measures to minimize damages are conducted from various perspectives. On the other hand, diffusion of knowledge of earthquakes to the general public is an important issue, since the knowledge of earthquake studies can contribute to the minimization of earthquake damages only when the results are fed back to society.I have engaged in research to contribute to society by reducing earthquake damages. My area of specialty is the study of active faults that are distributed throughout Japan, and since 1986, I have engaged in research in collaboration with the archaeological discipline that was unrelated to seismology. - A new interdisciplinary area between paleoseismology and archeology -Akira SangawaKansai Collaboration center, AIST Nakoji 3-11-46, Amagasaki 661-0974, Japan E-mail : Received original manuscript December 8, 2008, Revisions received January 23, 2009, Accepted January 28, 2009Traces of paleoearthquakes have been found at many archeological sites in Japan. However, most of them have been neglected to date and not considered to be a subject relevant to archeological research. The author has studied these traces since 1988, naming this new study field “Earthquake Archaeology”. The field has become popular both in archeology and paleoseismology and many important and useful results have been gradually obtained. These developments will lead to a deeper understanding of the natural and cultural history of the earthquake-prone country, Japan. Most paleoearthquake phenomena present at archeological sites manifest as liquefaction, lateral spreading and landslides. Detailed geological observations may also contribute to a reduction in damage caused by big earthquakes.A study of paleoearthquakes at archeological sitesKeywords : Earthquake archeology, archeological sites, trace of earthquake, active fault, liquefaction, Nankai Trough, Fushimi earthquake, Great Hanshin-Awaji earthquake[Translation from Synthesiology, Vol.2, No.2, p.91-100 (2009)]

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