Development of a Web Application System for Seismic Waveform Data Observed in Real Time With the Seafloor Seismic Network DONET.

Mega-thrust earthquakes are anticipated to occur in the Nankai Trough in Southwest Japan. In order to monitor seismicity, crustal deformations, and tsunamis in earthquake source areas, we deployed the seafloor seismic network DONET (Dense Ocean-floor Network System for Earthquakes and Tsunamis) in 2010 (Kaneda et al., 2015; Kawaguchi et al., 2015). The DONET system consists of a total of 20 stations that are composed of multiple types of sensors, including strong-motion seismometers and quartz pressure gauges. These stations are densely distributed at an average distance of 15-20 km and cover from near the trench axis to coastal areas. Observed data are transferred to a land station through a fiber-optic cable and then to the Japan Agency for Marine-Earth Science and Technology (JAMSTEC) data management center through a private network in real time. After the 2011 earthquake off the Pacific coast of Tohoku, each local government close to the Nankai Trough sought to devise a disaster prevention scheme. These local governments requested that JAMSTEC disseminate the DONET data along with other research capabilities so that they could exploit this important earthquake information. In order to provide local government access to the DONET data, which are recorded ostensibly for research purposes, we have developed a web application system, REIS (real-time earthquake information system), that provides seismic waveform data to some local governments close to the Nankai Trough. In the present paper, we introduce the specifications of REIS and its system architecture. [ABSTRACT FROM AUTHOR]