Vol.2 No.3 2009

Research paper : Evaluation of earthquake occurrence from active faults (T. Yoshioka)−182−Synthesiology - English edition Vol.2 No.3 (2009) AuthorToshikazu YoshiokaCompleted the master’s course in geography at the Graduate School of Science, Tokyo Metropolitan University in 1986. Joined the Geological Survey of Japan, Agency of Industrial Science and Technology, Ministry of International Trade and Industry in 1986. Obtained doctorate (Science) at Kobe University in 1995. Worked as Senior Researcher of Active Fault Research Center, AIST in 2001; Head of Active Fault Information Research Team in 2002; and Head of Active Fault Survey Team in 2004. Goes out in the field for geomorphological and geological survey of active faults, and has worked steadily on the prediction of future earthquakes from the survey results. Wrote and published the Rupture Probability Map of Major Active Faults in Japan in 2005 as the main author.Discussion with Reviewers1 The positioning as Full Research and descriptions in reference to “synthesiology”Question and comment (Masaaki Mochimaru, Digital Human Research Center, AIST)The positioning as Full Research is clearly stated in “1 Objective and background of the research.” The active fault research as a study in geomorphology and geology is Type 1 Basic Research, while the following active fault research for earthquake prediction is Type 2 Basic Research. The categorization of the active faults into behavioral segments using the Cascade Earthquake Model provided a breakthrough, and investigations were done for the Kinki region. Up to this point can be considered as Type 2 Basic Research. The survey was conducted nationwide and the results were published and presented to society. This can be positioned as Product Realization Research.However, as an academic journal, Synthesiology, we would like you to describe, with scientific eyes, the researcher’s dream of “what kind of society you wish to realize,” “why you selected” Paleoseismology, Academic Press, 439-493 (1996).Y. Awata: Nihon no jishin danso ni okeru segumento kozo to kasukedo moderu (shian) (Behavioral segments and their cascades for the earthquake occurrence in the Japanese surface ruptures - Tentative study) -, Chishitsu Chosasho Sokuho (Interim Report on Active Fault and Paleoearthquake Researches in 1998 Fiscal Year (GSJ Interim Report)), EQ/99/3, 275-284 (1999) (in Japanese).Active Fault Research Group, GSJ: Kinki sankaku chitai ni okeru katsudanso chosa (Active fault investigatiion in the Kinki Triangle: Paleoseismicity and earthquake potential of major active faults), Dai 4ki Kenkyu (Journal of Japan Association for Quaternary Research), 39, 289-301 (2000) (in Japanese).T. Yoshioka, Y. Awata, K. Shimokawa, Y. Sugiyama and Y. Fusejima: Zenkoku Shuyo Katsudanso Katsudo Kakuritsu Chizu (Rupture Probability Map of Major Active Faults in Japan), Geological Survey of Japan, AIST, (2005) (in Japanese).Y. Kase and S. M. Day: Spontaneous rupture processes on a bending fault, Geophysical Research Letters, 33, L10302 (2006).[6][7][8][9]the methods that lead to practical application of basic research to achieve the dream, and whether the selected method was “effective or not” in achieving the goal. The aim of Synthesiology is to build the “science of synthesis” by collecting the case studies of Full Research. Rather than just being a collection of papers, it is important that the individual papers are written with “synthesiology” in mind.Question and comment (Shigeko Togashi, Evaluation Division, AIST)I recommend this paper for publication in Synthesiologybecause it practices Full Research by conducting rupture probability prediction as Type 2 Basic Research based on the geological research of active faults and by contributing to society through the publication of results that may mitigate earthquake hazards. However, there is a lack of enough explanation, which will be indicated in Discussion 2, and there are points that should be added from the Synthesiology perspective. Please give the definitions of the terms such as active fault, fault, and earthquake-generating fault that were mentioned in the paper.Answer (Toshikazu Yoshioka)I added the description on the significance of this research for preventing earthquake disaster in the introduction of the paper. Also, I added the author’s thoughts in the conclusion as follows.“The author feels that our social responsibility is to organize the intellectual foundation that can be used to prepare against earthquakes, by presenting the prediction of active fault ruptures as accurately and as comprehensively as possible to society. Although presenting the information with sufficient accuracy or complete comprehensiveness cannot be realized immediately, I believe that the publication of the results on a nationwide scale is significant as the first step. Whether this research methodology was effective or not will be evaluated by how the society responds.”The word “active fault” is used widely in general, and its definition may differ according to people and situations. Therefore, I added a clear definition. The terms like earthquake-generating faults were deleted to avoid confusion.2 Selection of the research method and verification of its efficacyQuestion and comment (Masaaki Mochimaru)Please describe the selection of the research method and the verification of its efficacy as scientifically as possible. There are two points in this paper that are important in terms of synthesis. One is the application of Cascade Earthquake Model, and second is the nationwide survey and publication. For example, for the Cascade Earthquake Model, why did you consider using this model? Were there other models that could be used? Those are the important points in terms of synthesis. Of course, verification of the application of the Cascade Earthquake Model is also important.Similarly, what were the reasons for selecting the method of nationwide survey and publication? Were there any other methods? What social effects did you expect by widening the area from Kinki to all of Japan? What was the effect? Were there any academic byproducts? Why did you focus on the data from a single research institute rather than obtaining consensus through a committee? What “merits” did that method bring?, and so on. It will also be good if you summarize how much of the goal (dream) you initially set was achieved, what were the limits, and how you would overcome them.Question and comment (Shigeko Togashi)Please describe the principle of the Cascade Earthquake Model simply, and explain specifically why you selected this model, how it was developed into a numerical simulation, and the relationship to other models.For the limit of prediction, it is true that the accuracy of


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