Vol.9 No.2 2016
Research paper : Development of rock deformation techniques under high-pressure and high-temperature conditions (Koji MASUDA)−109−Synthesiology - English edition Vol.9 No.2 (2016) AuthorKoji MASUDACompleted the doctoral program in the Department of Earth and Planetary Sciences, Graduate School of Science, Nagoya University, and obtained the degree of Doctor of Science in 1987. Joined the Geological Survey of Japan, Agency of Industrial Science and Technology, Ministry of International Trade and Industry, in 1990. Specialties are geophysics of the Earth’s interior, seismology, and rock mechanics. Conducts research on the role of fluids in earthquake generation mechanisms and physicochemical processes by using the methods of rock mechanics. Deputy Director, Research Institute of Earthquake and Volcano Geology, AIST, since 2014.Discussions with Reviewers1 OverallComment (Chikao Kurimoto, AIST)Japan is positioned in one of the world’s most active belts of crustal movement and thus experiences frequent geological disasters. There is a demand to build a society that is resistant against earthquake disasters, and research on earthquake forecasting is essential. This paper addresses the challenging topic of how rock experiments are used to reproduce geological phenomena that occurred deep underground in the past and to verify an earthquake forecast model. This work integrates advanced technological developments and investigations of geological phenomena to understand the differences in spatial scale, structural conditions, and time between the laboratory and the natural world and presents a clear research scenario, and I think the paper is appropriate for publication in Synthesiology.Comment (Toshimi Shimizu, AIST)This research addresses experimental techniques and methods to accelerate and investigate rock deformation and fracture processes that progress on a thousand-year scale in the natural world. The work has been developed through the introduction and integration of original high-pressure and high-temperature technologies with a compression testing apparatus that has been used for general materials testing. It is extremely interesting that the effectiveness of this method was demonstrated by a laboratory experiment showing the adequacy of the hypothesis that when water is present, fault friction strength weakens over a long period of time. This paper is a case study that contributes social value by constructing a high-precision earthquake forecast model, and I think the content is appropriate for Synthesiology.2 Refinement of the earthquake forecast modelComment (Toshimi Shimizu)As a goal of this study, you mention the construction of a high-precision earthquake forecast model. I understand that the analysis of rock behavior and property changes based on accelerated tests under high temperature and high pressure can be helpful in investigations of earthquake occurrence mechanisms. However, I think that it is rather difficult to understand how the outcomes of this research can directly or indirectly help the general public prepare appropriately for an earthquake disaster. 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