Research on Pre-Modern Earthquakes Based on Fusion of Humanities and Sciences Masaharu Ebara∗,†, Akihito Nishiyama∗∗,Taisukemurata∗∗∗, and Reiko Sugimori∗

https://doi.org/10.20965/jdr.2020.p0076 Ebara, M. et al.

Survey Report: Research on Pre-Modern Earthquakes Based on Fusion of Humanities and Sciences Masaharu Ebara∗,†, Akihito Nishiyama∗∗,TaisukeMurata∗∗∗, and Reiko Sugimori∗

∗Historiographical Institute, The University of Tokyo 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan †Corresponding author, E-mail: [email protected] ∗∗Earthquake Research Institute, The University of Tokyo, Tokyo, Japan ∗∗∗Nara National Institute for Cultural Properties, Nara, Japan [Received October 18, 2019; accepted January 30, 2020]

The Great East Japan Earthquake and Tsunami has pilation of catalogs since the 1970s on these disasters reawakened people to the reality of large-scale earth- along the Japanese archipelago and its vicinity; these cat- quakes that recur in cycles of several hundred to a alogs continue to be supplemented and revised to this thousand years. The historical resources and arche- day [3]. Meanwhile, research to investigate earthquakes ology research group, which was established in 2014 that occurred in the past, including prehistoric times, within the Coordinating Committee of Earthquake by examining and collecting traces of damage discov- and Volcanic Eruption Prediction Researches, is col- ered during archeological digs around Japan, began in laborating with researchers of seismology, history, the 1980s [4]. Based on this research, several megath- archeology, and information science to investigate in- rust earthquakes along the Nankai trough and those orig- frequent earthquakes using historical documents that inating in inland active faults, before modern observa- record earthquakes and traces of disasters at archeo- tional instruments were available, were identified and elu- logical sites. To this end, we are creating a database of cidated. published historical sources of earthquakes to make However, such findings were mainly made by re- the data readily accessible, and reexamining these searchers in the fields of seismology and geology. In the sources and uncovering new historical material to in- field of historical science, following the Second World vestigate earthquakes that occurred in pre-modern War, events and actions revolving around human actors times. We are also engaged in research on relief efforts were considered as the main subject of study, with little for victims of past earthquakes and the post-disaster attention paid to natural or environmental history. Seis- reconstruction process. mology, too, saw very few historians getting involved. Furthermore, seismologic studies using damage traces such as sand volcanoes found at archeological sites were Keywords: disaster prevention, earthquake, pre-modern, mostly undertaken by only a handful of seismologists. historical material, archeology This situation changed after the March 11, 2011 Tohoku-oki earthquake – the occurrence of a large-scale megathrust earthquake, which had a frequency less than 1. Research on Historical Earthquakes Based the approximately 100-year observation period of mod- on Historical and Archeological Resources ern seismology, made many researchers aware of the need for accurate studies on historical earthquakes. Histori- Research to investigate earthquakes and volcanic erup- cal researchers had acutely felt the impact as well – al- tions that occurred before modern observational instru- though aware of articles describing earthquakes in histor- ments were invented, by using the descriptions recorded ical sources, they had failed to disseminate this knowl- in historical sources, began in Japan at the end of the edge to the society at large, which resulted in the founding nineteenth century. Earthquake-related historical sources of several study groups of historical earthquake sources were searched for and collected to build a research ba- around Japan. Such recognition, in 2014, led to the es- sis, as a result of which a total of 35 documents (approx- tablishment of the historical resources and archeology imately 28,000 pages) have been published since the be- research group within the Coordinating Committee of ginning of the twentieth century till now. These collec- Earthquake and Volcanic Eruption Prediction Researches tions list various historical sources related to each earth- (CCEVPR). It saw participation from representative re- quake that occurred around Japan in chronological or- search institutes in the fields of seismology and history as der [1, 2]. well as researchers in the fields of not only seismology Research on historical earthquakes based on modern and geology but also history and archeology. The frame- seismology has progressed as the collections of related work was thus designed to push forward seismic research historical sources have grown in number, leading to com- based on the collaboration of humanities and sciences.

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© Fuji Technology Press Ltd. Creative Commons CC BY-ND: This is an Open Access article distributed under the terms of the Creative Commons Attribution-NoDerivatives 4.0 International License (http://creativecommons.org/licenses/by-nd/4.0/). Research on Pre-Modern Earthquakes Based on Fusion of Humanities and Sciences

The first goal of the research group based on this collab- ϮϱϬ &ƵũŝŶŽŵŝǇĂ oration is to digitalize the published historical earthquake ^ŚŝǌƵŽŬĂ Kŵŝ sources. Although the previously published compilations ϮϬϬ dŽǇŽŚĂƐŚŝ are valuable resources for research, they are inconvenient dĂŚĂƌĂ for referencing because of the publication history, which /ƐĞ ϭϱϬ involves repeated supplementations. This can be resolved KŚŵŝŚĂĐŚŝŵĂŶ and the resources can be made easier to use through digi- <ǇŽƚŽ /ŬĞĚĂ ϭϬϬ talization and their incorporation into a database. <ŽĐŚŝ The second goal is to make use of the earthquake- dŽǇŽŽŬĂ dŽƚƚŽƌŝ related historical sources to obtain and accumulate knowl- ϱϬ edge on these disasters before modern instrumentation KŬĂǇĂŵĂ and the resulting damage, including the investigation and ,ŝƌŽƐŚŝŵĂϮ Ϭ ,ŝƌŽƐŚŝŵĂϭ gathering of historical sources not yet included in the /ǁĂŬƵŶŝ compilations. It is particularly important to gain an un- <ŽŵĂƚƐƵ derstanding of the writing processes of these historical /ŵĂďĂƌŝ sources and their natures to extract accurate facts rather than taking the descriptions on faith. In addition to the Fig. 1. Monthly number of felt earthquakes following the damage caused, research will also be undertaken to ex- 1854 Tokai and Nankai disasters. amine the post-disaster relief and reconstruction efforts of the past. In this process, attention needs to be paid to the correspondence between earthquakes as natural phenom- i. The number of days of felt earthquakes declined ena and activities of human society. gradually following the two major earthquakes, The third goal is to digitalize the information on dam- falling to five or less in most locations after the Third age traces confirmed at archeological sites and enter it into Month, Ansei 2, in western Japan and the Fourth a database. The construction of a system to employ arche- Month in eastern Japan. ological findings to conduct research on historical earth- ii. No earthquakes were felt at most locations in the quakes on an organizational and continual basis can be Eighth Month, Ansei 2. called an epochal event. iii. The number of felt earthquakes increased the fol- In this report, we review the main findings related to the lowing month, i.e., the Ninth, during which a strong second and third goals mentioned above obtained over the earthquake occurred on the 8th in western Japan and past five years. another that caused damage on the 28th in the Tokai region. 2. Investigation of Earthquakes Based on His- iv. In areas located in present-day Kochi prefecture, the number of felt earthquakes remained high until the torical Documents end of Ansei 2, when a decline was registered at last. 2.1. Felt Earthquakes Following the 1854 Tokai and Thus, the number of felt earthquakes following the Nankai Disasters Tokai and Nankai ones fell once, increasing immediately before the Edo earthquake. The 1854 Tokai earthquake, which occurred on De- cember 23, and the 1854 Nankai earthquake, which oc- 2.2. Date of the 1596 Bungo Earthquake curred the following day, have the most historical sources among all Nankai trough earthquakes that occurred in pre- 2.2.1. The Issue modern times. While many studies have been published There have been two theories since 70 years ago on the on the resulting damage and seismic intensities of various date of the Bungo earthquake, which occurred in Septem- locations, few focus on the tremors around Japan during ber 1596 (intercalary Seventh Month, Bunroku 5) and and after these earthquakes. In this study, we investigated caused a tsunami along the coast of Beppu Bay: the 9th felt earthquakes in various locations around Japan in the and 12th of the intercalary Seventh Month. Although the period beginning with these two earthquakes and ending difference is only of three days, if it can be established on November 11, 1855, when the 1855 Edo earthquake with certainty that the Bungo earthquake occurred on the occurred. The investigation was conducted in the follow- 9th, then the possibility exists that it was a large-scale dis- ing manner. aster that caused damage on both sides of the Hoyo Strait, The diaries and journals of feudal domain officials, vil- as there are records of earthquake damage in Iyo, located lage headmen, and merchants in locations spanning from across the Strait from Bungo, on the 9th. However, if the western Chugoku region to the eastern Tokai region it occurred on the 12th, it may have been a local earth- were examined, and the days on which earthquakes were quake. Indeed, the date of an earthquake can affect the felt identified. Then, the numbers of these days were tab- assessment of its scale. According to a recent theory, two ulated according to month. The findings are as follows separate earthquakes occurred on these two dates; how- (Fig. 1, dates according to the Japanese calendar): ever, there has been some misinterpretation of the histori-

Journal of Disaster Research Vol.15 No.2, 2020 77 Ebara, M. et al.

cal sources, and thus, the debate continues. In the present states the tsunami occurred on the 9th. In such cases, the study, we attempted to provide a conclusion by examin- proper thing would be to follow the source description. ing the nature of and relationship between the historical Thus, it appears that the descendants interpreted the pas- sources on which the two sides are based. sage, when quoting the biography, in light of the knowledge of the Kinai earthquake on the 12th, and modified the date accordingly, just as Tokura had done. 2.2.2. Historical Sources That Record the Date of the Chronology of Kitsuki in Oita [11], which falls un- Tsunami der (3), gives 12th as the date of the tsunami; yet, Essays The theory that the tsunami occurred on the 9th is of Suwa Kanson, which was used as a reference based on based on the following historical sources: Chronology its foreword, only notes that the tsunami occurred in the of Yusuhara Shrine [5] (hereafter Yusuhara Chronology), “seventh month,” with no date specified. The Colophon of the Great Perfection of Wisdom Su- Based on the above discussion, we conclude that, by tra [6], Biography of Shibayama Kanbe [7], Travel- tracing back and examining the sources of this historical ogue of Diplomatic Mission of Korean Dynasty [8], and material, Bungo Province does not have a reliable source Archives of the Miura Family [9]. These sources have in that records 12th as the date of the tsunami and earth- common the facts that they were written shortly after the quake. earthquake and contain descriptions of events in Bungo This gives rise to the following question: from which Province only, with no entries on earthquakes in other sources did Tokura and Kanbe’s descendants get 12th as places such as Kyoto. Furthermore, they appear to be in- the date of the Kinai earthquake? Although there are dependent records based on separate information sources. likely to be multiple sources, a notable one is Wakan This is an important point. Goun, a chronicle (printed using wooden movable type) Meanwhile, the theory that the tsunami occurred on whose first edition was published in Keicho 5 (1600). the 12th is based on Bungo Province sources that can It contains a passage that mentions the Kinai earthquake be broadly divided into three groups: (1) those writ- occurred on the 12th. This publication was a bestseller ten in “Funai” (present-day Oita city), (2) those written that saw several editions throughout the Early Modern in the Oka domain (present-day Bungotaketa city), and (Edo) period in Japan, and exerted a great influence on the (3) those written in the Kitsuki domain (present-day Kit- compilation of subsequent chronicles [12]. It is thus rea- suki city). It is certain that the sources in (1) are all sonable to assume that it had a direct impact on the occur- based on Chronology of Oita in Medieval Ages [10] (here- rence date’s modification by Tokura and the others. Fig. 2 after Oita Chronology). Oita Chronology is considered to shows the relationship between the above documents. have been compiled in Genroku 11 (1698) by a local merchant named Tokura Sadanori based on the founding his- 2.2.3. Date of the Earthquake in Historical Sources tories and biographs of the monks at temples and shrines Outside of Bungo Province within the domain; it contains four passages on Yusuhara The reason why the theory positing 12th as the occur- Shrine (Yusuhara Hachimangu) that give descriptions of rence date is supported even today, in spite of the above the historical sources kept by the Shrine even today as evidence, lies in the existence of several historical sources well as descriptions in common with Yusuhara Chronol- outside of Bungo Province that contain records mention- ogy. It is certain that Oita Chronology was written based ing the same. For instance, Diary of Fujiwara Seika in on an examination of these historical sources, suggesting Kyusyu Island [13], written by Fujiwara Seika, a famous Yusuhara Chronology was one of its sources. Confucian scalar, mentions that an “earthquake” occurred Comparing the descriptions of the earthquake in the on the 9th and “large earthquakes” on the 12th and 13th in two sources, with the above observation in mind, we Kagoshima prefecture, which have been previously inter- found that, on one hand, they contain similar distinc- preted to refer to the Iyo, Bungo, and Kinai earthquakes, tive expressions, and on the other, Oita Chronology dif- respectively. However, it is difficult to interpret that an fers from Yusuhara Chronology when referring to “the all earthquake that occurred in Kinai on the 13th could be Japan class giant earthquake (Tenka no Ohjishin),” stat- felt as a “large earthquake” in Kagoshima. Furthermore, ing that the tsunami occurred on the 12th. Considering there is no evidence to interpret the earthquake on the 12th the similarities and differences of the two sources, we as being the Bungo one. can speculate that Tokura had read Yusuhara Chronology Diary of Kokusai Gen’yo [14], written by Kokusai and, while borrowing some it is expressions, interpreted Gen’yo, one of poets, does contain a passage that states its earthquake article based on the then widely dissemi- that an earthquake and tsunami occurred on the 12th nated knowledge of the large-scale Kinai (five regions in at Saganoseki in Bungo Province. However, Gen’yo the vicinity of Kyoto) earthquake, which had occurred on was staying at Tonoura, located in the south of Hyuga the 12th, revising the date accordingly (Tokura also added Province, on the 12th, arriving in Saganoseki only 20 days a note referring to the theory that gives 9th as the date of later. It is possible that Gen’yo made this entry by super- occurrence). posing his Tonoura experience of the “large earthquake” The historical sources belonging to (2) are all those in Kagoshima onto the dreadful scene before him (in written by the descendants of Shibayama Kanbe, and have Bungo Province when he arrived). Since this possibil- as their source Biography of Shibayama Kambe,which ity cannot be denied, Diary of Kokusai Gen’yo cannot be

78 Journal of Disaster Research Vol.15 No.2, 2020 Research on Pre-Modern Earthquakes Based on Fusion of Humanities and Sciences

ZĞůĂƚŝŽŶƐŚŝƉďĞƚǁĞĞŶ ƌĞůĂƚĞĚŚŝƐƚŽƌŝĐĂůŵĂƚĞƌŝĂůƐ ŝŶKŝƚĂƉƌĞĨĞĐƚƵƌĞ ŚƌŽŶŽůŽŐǇŽĨKŝƚĂ ŚƌŽŶŽůŽŐǇŽĨ ,ŝƐƚŽƌǇŽĨ ŝŶDĞĚŝĞǀĂůŐĞƐ zƵƐƵŚĂƌĂ ^ŚƌŝŶĞ ƵŶŐŽ WƌŽǀŝŶĐĞ

ƚŚ dŚĞŽůŽƉŚŽŶŽĨ dŚĞŽƌǇŽĨϭϮ ĂŝŚĂŶ͛ŶǇĂ ^ƵƚƌĂ ZĞĨĞƌĞŶĐĞŵĂĚĞƚŽ ,ŝƐƚŽƌǇŽĨDĞĚŝĞǀĂůĂŶĚ ŽǁŶĞĚďǇ<ŽĚŽũŝ ͞ŐƌĞĂƚĞĂƌƚŚƋƵĂŬĞŝŶ WƌĞŵŽĚĞƌŶŐĞƐKŝƚĂ dĞŵƉůĞ ǀĂƌŝŽƵƐƉƌŽǀŝŶĐĞƐ͟ dŚĞŽƌǇŽĨϵƚŚ ŝŽŐƌĂƉŚǇŽĨ ,ŝƐƚŽƌǇŽĨ/ƚŽŬƵũŝ dĞŵƉůĞŝŶKŝƚĂ EŽƌĞĨĞƌĞŶĐĞ ^ŚŝďĂǇĂŵĂ ^ŚŝŐĞƐƵŬĞ ŵĂĚĞƚŽŽƚŚĞƌ 'ĞŶĞĂůŽŐǇŽĨ ůŽĐĂƚŝŽŶƐ dƐƵǇĂŵĂ &ĂŵŝůǇ ŚƌŽŶŽůŽŐǇŽĨKŬĂ ŝŽŐƌĂƉŚǇŽĨ ŽŵĂŝŶ ^ŚŝďĂǇĂŵĂ <ĂŵďĞ ŝŽŐƌĂƉŚǇŽĨdŽŬŝ&ĂŵŝůǇ ƌĐŚŝǀĞƐŽĨ DŝƵƌĂ&ĂŵŝůǇ ,ŝƐƚŽƌǇŽĨƚŚĞKŬĂ ŽŵĂŝŶ

ƐƐĂǇŽĨ^ƵǁĂ ŚƌŽŶŽůŽŐǇŽĨ<ŝƚƐƵŬŝ <ĂŶƐŽŶ tĂŬĂŶ'ŽƵŶ ;ŚƌŽŶŽůŽŐǇ ŽĨŚŝŶĂĂŶĚ:ĂƉĂŶͿ ŽŬƵ ,ŽŶĐŚŽdƐƵŐĂŶ ;^ĞƋƵĞůƚŽ,ŝƐƚŽƌǇŽĨ:ĂƉĂŶͿ

Fig. 2. Diagram showing the relationship between historical documents on the Bungo earthquake.

considered as irrefutable evidence that the earthquake oc- 3. Reconstruction After the 1855 Edo Earth- curred on the 12th. quake (Ansei Edo Jishin) Meanwhile, A Report concerning the Kingdom of Japan (Relacion´ del Reino de Nippon a que llaman cor- The 1855 Edo earthquake occurred around 10 p.m. on ruptamente Jappon) [15], written by Avila Giron, a Span- November 11, with its epicenter located in the northern ish merchant who resided in Nagasaki, contains an en- part of Tokyo Bay; its magnitude is estimated to have try that refers to “Humfama, Hyuga” being inundated been 7.0–7.1 and peak seismic intensity 6 [3]. It caused on the 12th. Previously, this has been interpreted as er- extensive damage and resulted in over 7,000 deaths in roneous, and it has been suggested that Okinohama in Edo [17], which was the seat of the Shogunate (Bakufu) Bungo Province be referred to instead, to make the pas- and had a population of over a million. sage about the Beppu Bay tsunami. However, if we take The Shogunate implemented three relief measures: the this historical account at face value, it should be inter- establishment of relief centers to provide those rendered preted as being a reference to Uenohama (or Uenhama) homeless a place to sleep and eat, emergency rice feeding near Shibushi (located in present-day Kagoshima prefec- programs, and the distribution of relief rice [18]. ture but was in Hyuga Province historically). In this case, For this section, we tracked the Shogunate’s relief ef- it should be considered unrelated to the Bungo earth- forts from records kept by senior town administrators and quake. examined historical paintings to grasp the real situation, for a glimpse of how reconstruction proceeded following 2.2.4. Which Earthquake Occurred on the 12th? the earthquake. Based on the above considerations, we conclude that the earthquake that resulted in tsunami damage in Beppu 3.1. Shogunate’s Relief Efforts Based on Records of Bay occurred on the 9th. What then was felt at various Senior Town Administrators locations in Kyushu on the 12th? The earthquake on the Saito Yukishige (Gesshin) (1804–78), the town admin- 12th is also recorded in reports [16] written by Jesuit mis- istrator of Kijicho (present-day Kanda Tsukasa Machi sionaries and European merchants. The locations where 2 Chome, Chiyoda Ward), has left us a diary (Diary of tremors were reportedly felt on the 12th, including those Saito Gesshin [19]) that covers 37 years during the pe- that incurred damage as noted in these sources, are Na- riod 1830–76. In it are records of the daily weather, his gasaki, Shimabara Peninsula, central Higo Province, and ofﬁcial duties as the town administrator, his and his fam- present-day Kagoshima prefecture, in southwest Kyushu. ily members’ actions, and events such as ﬁres and earth- Although there is need for further investigation, the earthquakes. quake that occurred on the 12th was perhaps centered in Meanwhile, based on several thousand documents kept southwest Kyushu. by his family since the Meireki era (1655–58), Takano Naohiro (1817–70), the town administrator of Minami Denmacho 2 Chome (present-day Kyobashi 2 Chome, Chuo Ward), completed the compilation of Senyo Eikyu

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Roku [20], which he acquired from his predecessor and • The representative of each household accepting the records the “machibure” (laws and regulations issued relief rice, based on the submitted list, must prepare against town residents) of Edo, duties as the “tenma- a container for it. yaku” (corvee assignment of supplying horses to post sta- • The town administrator must accompany the rep- tions), and town policies. resentatives and report to the machi-kaisho office Both men supervised several towns including those at 6 a.m. on January 17, regardless of the weather. they resided in, and were also representatives of town administrators of their respective areas; hence, their diaries After Takano arrived at the office on the specified date, ac- and compilations present valuable records of historic Edo. companied by the representatives from the five townships under his jurisdiction, they were called according to their residence, beginning with Minami Denmacho 2 Chome; 3.1.1. From Emergency Rice Feeding to Relief Rice the amount of rice given was based on the number of fam- Distribution ily members, and the rationing was completed sometime According to Diary of Saito Gesshin, the “machi past noon. kaisho” office began distributing rice balls (nigiri-meshi) The rationing was based on the following criteria: each immediately after the 1855 Edo earthquake, and then set male aged between 15 and 59 received five sho (approx- up relief shelters (osukui-goya) on November 14, which imately 9 liters), while each male aged between three were gradually increased in number. The purpose behind and 14, and 60 and above, as well as each female received these measures was to provide relief to those who had lost three sho (approximately 5.4 liters). The 453 who lived their homes in the earthquake or subsequent fires and were in the five townships under Takano’s jurisdiction received forced to sleep in the open. rice for 1,568 people. On November 21, however, because the emergency rice feeding was found wanting at some locations, the office 3.1.3. Walking Through Snow-Covered Streets put forth an inquiry as to whether it would be better to dis- tribute uncooked rice instead, and whether stopping the The representatives in townships under Gesshin’s ju- distribution of rice balls would cause problems (Senyo risdiction received their ration on January 28. It began Eikyu Roku); Takano and Gesshin both submitted their snowing before dawn the previous day, which continued replies on November 23, based on which, the office de- throughout the day and into the night (Diary of Saito cided to halt the distribution of rice balls from Novem- Gesshin), covering the ground with 30 cm of snow [23]. ber 29, and notified the town administrators to conduct Although this made walking difficult, Gesshin reported to a survey of the destitute population under their respec- the office accompanied by the representatives. tive jurisdictions, and create and submit a list of names of Even on the day of the heavy snowfall, residents of those in need (Senyo Eikyu Roku). The criterion for deter- Minami Shinagawa (present-day Minami Shinagawa, Shi- mination of the destitute was “daily wage earners (sonohi- nagawa Ward) had to report to the office for their rice [21] kasegi no mono),” and thus was not restricted to victims as the date had been assigned to them in advance. The of the earthquake. office was located about 10 km as the crow flies from After conducting an inspection tour of the six town- Minami Shinagawa, and it is recorded that the represen- ships under his jurisdiction, including Kijicho, Gesshin tatives talked among themselves about how they had suf- submitted the list of names on December 20; he continued fered from the earthquake earlier and now they had to suf- to make the rounds of those to be targeted for rice distri- fer again (because of the snow). bution in the neighboring townships under the jurisdiction The rice they had to carry back home from the office of other town administrators, and accordingly revised the weighed at least 4.5 kg per person (the weight of the three submitted list. This was because he had been instructed sho of rice allotted to one person), and in some cases, ex- to avoid differential treatment among the townships. ceeded 20 kg, depending on family size. One can image The distribution of rice ration thus began on Decem- their hardship in carrying such weight on their backs, and ber 23 [21], while a notification had been issued that new thus, their lamentations about their ordeals caused by the admittance to the relief shelters would not be accepted snow in addition to the earthquake are quite understand- from December 28 [22]. In this manner, the Shogunate’s able. relief efforts began with emergency rice feeding, followed by establishment of relief shelters, culminating with rice 3.1.4. Scale of Relief Rice Distribution distribution. The rice distribution was terminated on January 31, 1856. It is recorded that about 381,200 people received 3.1.2. Distribution Method of Relief Rice the relief rice rations in Edo [21], which is close to 70% According to Senyo Eikyu Roku, the machi-kaisho of- of the town population. fice issued advance instructions to the town administrators Assuming that each family representative received rice with regard to the date and procedure of rice distribution; for 3.46 persons, as in the case of residents of Takano’s Takano received the same on January 15, 1856, two days townships, it can be estimated that some 110,000 reported before he was to report to office. It comprised the follow- to the machi-kaisho office to receive the rice in Edo – this ing items: means close to 3,000 people daily; this situation lasted

80 Journal of Disaster Research Vol.15 No.2, 2020 Research on Pre-Modern Earthquakes Based on Fusion of Humanities and Sciences

Source: EdoOhjishinnoZu Source: EdoOhjishinnoZu(Shimazu family document owned by Historiographical Institute, The University of Fig. 4. Poles extending out into the street. Tokyo)

Fig. 3. Procession in snow.

for over a month. Although it must have been a common sight on the streets of Edo, no printed material on this has been found.

3.2. Reconstruction Process Seen in Edo Ohjishin no Zu (Picture Scroll Depicting the 1855 Edo Earthquake) Among the archives of the Shimazu family of the Sat- suma domain is a picture scroll1 called Edo Ohjishin no Zu [24, 25]. Depicted in it are scenes of Edo before and after the 1855 Edo earthquake. Source: Akita-gun Takahashi-machi Aza Kawabata Kaoku 3.2.1. Procession in Snow Houkai no Kei (Scene of House Collapse in Aza Kawabata, Takahashi town, Akita-gun) The scene of a procession, as shown in Fig. 3, can be Photo courtesy the National Museum of Nature and Science seen just before the end of the scroll, which has been identified as one describing the events of early February 1856. Fig. 5. Town scenery following the 1889 Kumamoto earthquake. The scene depicts a procession of people led by a person carrying a flag that indicates a town close to the Shiba residence (in Edo) of the Satsuma domain. Carrying pack- ages in their hands, they appear to be forming lines ac- 3.2.2. Poles Extending Out into the Street cording to townships, which corresponds to the manner The picture shown in Fig. 3 and another (Fig. 4)that in which they received relief rice, as described in Sec- precedes it in the scroll depict poles extending out into tion 3.1.2. the street. The practice of using poles to shore up tilted Furthermore, the snowfall has stopped, and several men houses was widespread from an early stage following from the procession can be seen making a snowman taller the earthquake, and created obstacles for the street traf- than them. Since the snow that fell on January 27 led to fic [21]. a 30 cm thick cover, which is said to have remained for a A similar scene is recorded in a picture (Fig. 5)ofa month (Diary of Saito Gesshin), the giant snowman was town section following the 1889 Kumamoto earthquake, likely made after that record-breaking snowfall. which occurred on July 28. Its epicenter was near Mount Because there were actual townships such as Minami Kinpo, located west of Kumamoto city, and it had a mag- Shinagawa whose residents had to make the trip to the nitude of 6.3 with a maximum seismic intensity of 6. The machi-kaisho office and back while it was snowing, the stone wall of Kumamoto Castle partially collapsed, and depicted procession appears to be a valuable record, based some 560 houses were partially or completely destroyed; on actual facts, of people who are on their way to receive of these, 265 were in Akita-gun (present-day Nishi Ward, their rice ration in heavy snowfall. Kumamoto city, and its vicinity) where the damage was most extensive [3]. The scene of Akitagun depicted in 1. Another scroll comprising pictures with identical configurations, previously owned by the Konoe family, is currently owned by the Chester Fig. 5 is quite similar to that in Fig. 4. Beatty Library in Dublin. The scene shown in Fig. 5 was captured within two

Journal of Disaster Research Vol.15 No.2, 2020 81 Ebara, M. et al.

Table 1. Felt earthquakes during the two-month period following the 1855 Edo earthquake.

Diary of Saito Gesshin Yabure Mado no Ki Diary of Saito Gesshin Yabure Mado no Ki 7HQWK (OHYHQWK 0RQWK ,QWHQVLW\ )UHTXHQF\ ,QWHQVLW\ )UHTXHQF\0RQWK ,QWHQVLW\ )UHTXHQF\ ,QWHQVLW\ )UHTXHQF\ VW ˕˕ QG ˖ $ERXW ˖ QG UG ˕ 2IWHQ ˕ UG ˘˕ WK ˘ 2IWHQ ˕ WK WK ˕ 2IWHQ ˕ WK WK ˕ Ը WK WK ˖ 2IWHQ ˖ WK WK ˕˕ WK WK ˕˕ WK WK ˕ DURXQGPLGQLJKW ˕ WK ˘˕ WK ˕ ˕ WK ˕ WK Ը ˕ WK ˕˕ WK ˕˕ WK WK ˕˕ WK ˕ WK ˕˕ WK ˕ ˕ WK ˕ 6SRUDGLF ˕ WK ˕ WK ˘˕ WK ˕ ˕ WK ˕˕ WK WK ˕˕ WK ˕ ˕ WK ˕ 'D\1LJKW ˕ WK VW ˕˕ VW QG ˕˕ QG UG ˕ UG ˕˕ WK ˕˕ WK ˕˕ WK ˕˕ WK ˕ WK ˕˕ WK WK ˕ WK WK ˕ WK WK ˕ ˕ WK WK ˕ ˕ The tremors are classiﬁed into •: large earthquake, • : moderate earthquake, : small earthquake, and ♦: earthquake based on the descriptions in Diary of Saito Gesshin and the size of circles in Yabure Mado no Ki. Dates are according to the lunar calendar.

weeks of the earthquake, and is among the earliest pic- a continual basis consist of entries with limited locations, tures of the resulting damage in Japan. It is, therefore, provide long-term information of earthquakes based on a visual historical record that provides a reference frame the standards of the individual, and also record felt earth- for the Edo earthquake, which had occurred 34 years ear- quakes that caused no damage. lier. It also confirms the value of EdoOhjishinnoZuas a When the entries of Diary of Saito Gesshin for the two- pictorial historical record. month period following the 1855 Edo earthquake were compared with those (Yabure Mado no Ki (Records from a Broken Window)2) that kept a record of tremors felt in a 3.2.3. Decrease in Poles certain samurai residence and listed them by their size (by In EdoOhjishinnoZu, in which the picture shown in the size of circles) and frequency, it was found that the two Fig. 3 comes after the one in Fig. 4, there appear fewer records mostly agreed on the dates of the earthquake, as poles and temporary shelters built in front of houses, as shown in Table 1, each confirming the other’s reliability one moves through the scroll. The sequence of pictures as a historical source. Although it is difficult to make an appears to reflect the process of reconstruction that took accurate comparison of the number of tremors, it is possi- place within the limits of Edo town during the three- ble to get a feel of the tremors that occurred following the month period after the earthquake occurrence. 1855 Edo earthquake from the graphical representation of the number of felt earthquakes recorded in Yabure Mado 3.3. Potential Value as Earthquake Historical no Ki,showninFig. 6. Source The Collaborative Research Organization for Histor- ical Materials on Earthquakes and Volcanoes, which As the above descriptions show, diaries and pictorial materials have the potential of being used as earthquake 2. Owned by the National Archives of Japan. Articles of the Tenth Month, historical sources that can convey the process of recon- Ansei 2, are also found in other historical sources but, to the authors’ knowledge, only the copy of Yabure Mado no Ki owned by the National struction. Of these, diaries written by a single person on Archives covers the Eleventh Month as well.

82 Journal of Disaster Research Vol.15 No.2, 2020 Research on Pre-Modern Earthquakes Based on Fusion of Humanities and Sciences

ϭϮ

ϭϬ

Ϭ ϰƚŚ ϲƚŚ ϴƚŚ ϱƚŚ ϳƚŚ ϵƚŚ ϯƌĚ ϮϭƐƚ ϭϬƚŚ ϭϮƚŚ ϭϰƚŚ ϭϲƚŚ ϭϴƚŚ ϮϬƚŚ ϮϮƚŚ ϮϰƚŚ ϮϲƚŚ ϮϴƚŚ ϭϭƚŚ ϭϯƚŚ ϭϱƚŚ ϭϳƚŚ ϭϵƚŚ ϮϱƚŚ ϮϳƚŚ ϮϵƚŚ ϮϯƌĚ ϮŶĚ͕dĞŶƚŚDŽ͘ ϭƐƚ͕ůĞǀĞŶƚŚDŽ͘

Source: Yabure Mado no Ki, dates according to the lunar calendar

Fig. 6. Number of felt earthquakes recorded in Yabure Mado no Ki.

was jointly established in April 2017 by the Earth- at which earthquake traces were detected” by the Rescue quake Research Institute and Historiographical Institute and Coordinating Committee on Buried Cultural Proper- of The University of Tokyo, is in the process of build- ties and the Society for the Study of Buried Cultural Prop- ing a database by extracting records of felt earthquakes erties, and the findings collectively published in the form from Diary of Saito Gesshin and other historical di- of a reference book [31]. aries, and incorporating this information in the geographic The Great East Japan Earthquake and Tsunami, which information system to construct a temporal-spatial dis- occurred in March 2011, provided impetus for a renewed tribution map of felt earthquakes, which is available recognition of the importance of learning from historical on its website (http://www.eri.u-tokyo.ac.jp/project/eri- disasters. In particular, emphasis was placed on a general hi-cro/database/index.html). thrust to survey, analyze, and study traces of large earthquakes and volcanic eruptions occurring at low frequen- cies as well as traces of disasters that accompanied those 4. Examination of Historical Earthquakes by phenomena, and verify the time and scale of their occur- Using Archeological Materials rence, especially with an eye on disaster prevention and mitigation. As a result, increasing attention was paid to 4.1. Emergence of Seismoarchaeology and Current traces of historical disasters in archeological excavations. Undertakings Against this backdrop, the Nara National Research In- stitute for Cultural Properties (NNRICP) and National In- It was from the 1970s that traces of past earthquakes stitutes for Cultural Heritage joined CCEVPR to partic- began to be confirmed through archeological excavations ipate in its research activities by creating a database of and subjected to scientific inquiry [26]. The number of ex- information on disaster traces around Japan, to use it for cavations increased drastically in Japan around that time disaster research as well as disaster prevention and miti- due to a construction boom. In the mid-1980s, traces gation efforts. of earthquakes such as sand volcanoes and ground fis- sures were successively discovered at archeological sites in Saitama, Gunma, Shiga, and Kyoto prefectures and re- 4.2. Creation of Database Combining Historical ported [27, 28]. It was around this time that reports of and Archeological Resources earthquake traces were presented at archeology-related conferences, and the interdisciplinary field of “seismoar- To promote multifaceted, wide-area research on histori- chaeology” was proposed [29, 30]. cal earthquakes, it is not enough to create a database com- This field or the existence of earthquake traces at arche- prising digitalized individual historical sources; in fact, an ological sites thus gained wider recognition, even as ex- integrative database is necessary (Fig. 7). Construction cavations around the country steadily grew in number, in- of the earthquake historical resource database is under- creasing the store of knowledge in this area. Yet, no re- way through the referencing of several existing historical ports were published that presented an overall summary source databases. However, since no database on disaster of the findings across Japan. This situation changed dras- traces has been created in the past, efforts are being taken tically after the 1995 Hanshin-Awaji Earthquake, which to create one by extracting and analyzing articles on them acted as the trigger for the renewed recognition of the sig- from excavation reports of sites around Japan, designing nificance of research on earthquake traces discovered at the database items, collecting information at archeologi- archeological sites; thus, in 1996, 378 archeological sites cal sites, and creating a distribution map of disaster traces in Japan were together classified as “archeological sites (Fig. 8).

Journal of Disaster Research Vol.15 No.2, 2020 83 Ebara, M. et al.

Fig. 7. Outline of the system for constructing a disaster trace database.

Fig. 8. Structural model of the disaster trace database.

Traces of sand volcanoes caused by liquefaction are 4.3. Visualization of Historical Earthquakes Using particularly important in the investigation of earthquake Database history. Liquefaction occurs readily in plains and basin bottoms, which have provided the living environment for We have created an alpha-version prototype of the humans through the ages. In addition to observation of database that combines the disaster trace and historical sedimental structure in ﬁeld working, NNRICP has re- resources databases, and used it to create a visual repre- cently begun collecting geological segmenting samples, sentation of the historical earthquakes that caused dam- which preserve the sediment structure, to carry out struc- ageintheNaraBasin(Fig. 9). The earthquake that oc- tural observations using soft X-ray radiography and mi- curred on July 26, 1361 (24th, Sixth Month of Koan 1), crofocus X-ray computer tomography. considered a megathrust one originating along the Nankai trough, caused damage to and collapse of structures such as Horyuji, Yakushiji, and Toshodaiji temples in the Nara Basin. Because the remaining historical resources are

84 Journal of Disaster Research Vol.15 No.2, 2020 ᅗ

Research on Pre-Modern Earthquakes Based on Fusion of Humanities and Sciences

References: [1] Earthquake Research Institute (Ed.), “New collection of Historical Materials on Earthquakes in Japan,” Volume 1-27, 1981-1994 (in Japanese). [2] T. Usami (Ed.), “Historical Materials on Earthquakes in Japan, Ad- dendum,” Volume 1-4, 1998-2012 (in Japanese). [3] T. Usami (Ed.), “The Catalogue of Disaster Earthquake in Japan 599–2012,” University of Tokyo Press, 2013 (in Japanese). [4] A. Sangawa, “Seismoarchaeology,” Chuokoron-Shinsha, 1992 (in Japanese). [5] “Chronology of Yusuhara Shraine,” Transcription book owned by Historiographical Institute (in Japanese). [6] Headquarter for Earthquake Research Promotion, “The Report of the Headquarter for Earthquake Research Promotion 2014-2016,” ᅗ ୡ⣖ࡢዉⰋ┅ᆅ࡟࠾ࡅࡿᆅ㟈⿕ᐖࡢⓎ⏕ሙᡤ࡜ 2017 (in Japanese). ⅏ᐖ⑞㊧Fig. 9. Locations of damage due to earthquakes that oc- [7] “Biography of Shibayama Kanbe,” Transcription book owned by curred in the fourteenth century and disaster traces in the owned by Historiographical Institute (in Japanese). Nara Basin. [8] T. Kuno, “Travelogue of Diplomatic mission of Korean Dynasty, 1596,” The Bulletin of Saga Prefectural Nagoya Castle Museum, ௒ᚋࡢ◊✲ィ⏬ Vol.25, 2019 (in Japanese). [9] “Archives of the Miura family,” owned by Oita City Historical Mu- seum (in Japanese). limited, the locations of damage they identify are also [10] “Chronology of Oita in Medieval Ages,” owned by National Diet limited to the temples in the basin’s northern part. Yet, Library (in Japanese). [11] “Chronology of Kitsuki Cty in Bungo Province,” owned by National archeological sources show that fourteenth-century disas- Diet Library (in Japanese). ter traces are extensively distributed in the basin’s south- [12] A. Katagiri, “A Study on Revision of the chronology of China and Japan,” Proc. of the 35th Meeting of the Society of Historical Earth- ern part. These are believed to be a result of the 1361 quake Studies, 2018 (in Japanese). earthquake, indicating that it is possible to identify the ge- [13] “Diary of Fujiwara Seika in Kyusyu Island,” H. Ohta et al. (Eds.), ographical extent of the ground tremor, which is not found “The Collection of Works by Fujiwara Seika,” Volume 2, Shi- bunkaku Co., Ltd., 1978 (in Japanese). in the historical documents. [14] “Diary of Kokusai Gen’yo,” “Gunsho-Ruiju,” Volume 325 (in Japanese). [15] B. de Abira Giron, “The Report concerning Kingdom of Japan,” T. Sakuma et al. (Trans.), The series of Great Voyage Era, Vol.1, 5. Future Research Plan No.11, Iwanami Syoten, 1965 (in Japanese). [16] T. Matsuda (Ed.), “Annual report by Louis Frois 1596,” Jesuit mis- sionaries reports on Japan in 16–17 century, Vol.1, No.2, Dobosya The historical resources and archeology research group Syuppan, 1987 (in Japanese). has adopted the following plan for future research: [17] Y. Nagura (Ed.), “Diary of Kakegawa Domain in Edo written by Watanabe Yoshiaki,” Seibundo Shuppan, 1995 (in Japanese). i. High-precision optical character recognition technol- [18] I. Kitahara, “The 1855 Edo earthquake and the people,” San-Ichi Publishing Inc., 1983 (in Japanese). ogy will be used to continue the digitalization process [19] Historiographical Institute The University of Tokyo (Ed.), “Diary of previously published historical resources. of Saito Gesshin: Series of Dainihon Kokiroku,” Iwanami Shoten, ii. Based on the digitalized earthquake-related historical 1997-2016 (in Japanese). [20] N. Takano and N. Takano, “Senyo Eikyuroku,” owned by Tokyo sources, analysis of pre-modern earthquakes will be Metropolitan Archives (in Japanese). carried out from various angles. The analysis results [21] G. Saito, “Buko Chido no ki,” owned by National Diet Library (in will be presented in the form of graphs and maps, Japanese). [22] “Shinsai Doyo ki,” owned by National Diet Library (in Japanese). and released to the public in an easy-to-understand [23] G. Saito, M. Kaneko (Ed.), “Chronology of Edo,” Heibonsha, 1968 format. (in Japanese). [24] “Archives of the Shimazu family,” owned by Historiographical In- iii. Historical documents that have not been previously stitute The University of Tokyo (in Japanese). included in published collections will be investi- [25] R. Sugimori, “The Picture Scroll Depicting the 1855 Edo Earth- gated, and research conducted on the conditions un- quake included in the Archives of the Shimazu family,” Report of the Center for the Study of Visual Sources, an affiliate of the Histo- der which the earthquakes occurred, damage status, riographical Institute, Vol.78, pp. 2-22, 2017 (in Japanese). as well as post-disaster reconstruction process, from [26] Y. Matsushima and N. Ban, “The Jomon Dwelling Site Displaced by the Itoigawa-Shizuoka Tectonic Line, Southeast of Lake Suwa, which lessons can be culled for future relief efforts. Central Japan,” The Quaternary Research, Vol.18, No.3, pp. 155- iv. Through the network of relevant organizations in 164, 1979 (in Japanese). Japan, the process of information collection for dis- [27] M. Horiguchi et al., “Ancient earthquake traces excavated on the archeological site of Fukaya Bypass in Saitama prefecture,” The aster trace data based on archeological findings will Bulletin of Saitama University Natural Science, Vol.21, 1985 (in be accelerated. Japanese). [28] A. Sangawa et al., “Ancient earthquake traces excavated on v. A comprehensive data search system for historical the archeological site of Kitoge-Nshigaito in Shiga prefecture,” and archeological resources will be implemented. Chishitsu News, Geological Survey of Japan, No.390, 1987 (in Japanese). During the previous planning period, we were unable [29] K. Hirose et al., “Ancient earthquake traces excavated on the archeological site of Nishi-Konoike in Higashi-Osaka city,” Summary of to address issues such as the collaboration with tsunami the Annual Meeting of Japanese Archaeological Association, 1988 trace surveys, or the survey and research of historical re- (in Japanese). [30] A. Sangawa, “Proposal of Seismoarchaeology,” Annual Report of sources on volcanic eruptions. We aim to tackle these in Japan Society for Scientific Studies on Cultural Properties, No.16, the present plan. In addition, we will disseminate our find- 1988 (in Japanese). [31] Liaison Council for Rescue of Buried Cultural Properties and The ings among researchers of history with the expectation of society of Buried Cultural Properties (Ed.), “Excavated Earthquake raising their level of interest in seismic research. Traces,” 1996 (in Japanese).

Journal of Disaster Research Vol.15 No.2, 2020 85 Ebara, M. et al.

Name: Name: Masaharu Ebara Taisuke Murata

Afﬁliation: Afﬁliation: Professor, Historiographical Institute, The Uni- Researcher, Archaeological Research Methodol- versity of Tokyo ogy Laboratory, Center for Archaeological Oper- ations, Nara National Research Institute for Cul- tural Properties

Address: Address: 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan 2-9-1 Nijo-cho, Nara-shi, Nara 630-8577, Japan Brief Career: Brief Career: 1980- Graduate School of Humanities, The University of Tokyo 2007- Graduate School of Frontier Sciences, The University of Tokyo 1983 Joined Historiographical Institute, The University of Tokyo 2009- Archaeological Research Center, Tottori Prefectural Office Selected Publications: 2014- Archaeological Research Methodology Laboratory, Center for • M. Ebara, “Muromachi Shogunate and Local Societies,” Iwanami Archaeological Operations, Nara National Research Institute for Cultural Syoten, 229pp., 2016 (in Japanese). Properties Academic Societies & Scientific Organizations: Selected Publications: • Historical Science Society of Japan • T. Murata, Geological studies, “Excavations of the Imperial Audience • Historical Society of Japan Hall Compound (Nos. 195, 198). II-1 Excavations at the Fujiwara Palace Site. II Excavation at the Asuke and Fujiwara Palaces and Other Sites,” Bulletin of Nara National Research Institute for Cultural Properties, pp. 76-84, 2019 (in Japanese). • T. Murata, “The database of paleodisaster records based on archaeological, stratigraphical, and historical studies in Japan,” Nara Name: National Research Institute for Cultural Properties (Ed.), “New digital Akihito Nishiyama technology and methods application to cultural properties,” pp. 159-192, Kubapuro Inc., ISBN978-4-905338-87-1, 2018 (in Japanese). Affiliation: Academic Societies & Scientific Organizations: Assistant Professor, Earthquake Research Insti- • Geological Society of Japan (JGS) tute, The University of Tokyo

Name: Address: Reiko Sugimori 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan Brief Career: Affiliation: 2007 Completed Graduate School of Letters, Otani University Associate Professor, Historiographical Institute, 2009 Joined Earthquake Research Institute, The University of Tokyo The University of Tokyo Selected Publications: • T. Harada, A. Nishiyama, K. Satake, and T. Furumura,“The Hyuga-nada Earthquake on June 30th, 1498 is a Fake Earthquake –Examination of the Damage Descriptions in the War Chronicle Kyushu-gunki–,” ZISIN (J. of the Seismological Society of Japan. 2nd ser.), Vol.70, pp. 89-107, doi: 10.4294/zisin.2016-13, 2017 (in Japanese with English abstract). Address: Academic Societies & Scientific Organizations: 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan • Seismological Society of Japan (SSJ) Brief Career: 1992- Graduate School of Humanities and Sociology, The University of Tokyo 1994 Joined Historiographical Institute, The University of Tokyo Selected Publications: • R. Sugimori, “Study on Edo Ohjishin no Zu (picture scroll depicting 1855 Edo Earthquake),” Kadokawa, 261pp., 2020 (in Japanese). Academic Societies & Scientific Organizations: • Historical Society of Japan

86 Journal of Disaster Research Vol.15 No.2, 2020