NEC Corporation, a leading network, communications and information technology company, announced today its deployment of the Dense Oceanfloor Network System for Earthquakes and Tsunamis (DONET) for the Japan Agency for Marine-Earth Science and Technology (JAMSTEC).
DONET is a high precision submarine network observation system off the coast of Japan's Kii Peninsula that helps understand and forecast earthquakes that take place in the densely populated Tonankai region. The system is located between 2,000 and 4,000 meters beneath the sea and composed of an optical submarine cable loop featuring branching units with node interfaces, state-of-the-art seismograph and water pressure meters for detecting tsunamis.
DONET's distinguishing features include its high density undersea observation points, low noise/wide frequency band and its ability to detect a large/dynamic range of changes in ground movement and water pressure. Furthermore, its observation equipment may be easily exchanged and updated with the latest measurement technologies.
Measuring device observations are delivered in real-time twenty four hours a day via the submarine cable's optical fiber. Data is first sent to a ground-based station in Mie prefecture where it is then relayed for analysis to institutions that include the Japan Meteorological Agency, the National Research Institute for Earth Science and Disaster Prevention (NIED) and a range of universities. These observations are expected to make valuable contributions to the speed and accuracy of earthquake and tsunami warnings as well as the improvement of earthquake prediction models.
This system is a result of research contracted to JAMSTEC for "development of a submarine network system" by the Ministry of Education, Culture, Sports, Science and Technology, and represents part of the Ministry's research on "construction of an earthquake and tsunami observation system" that has been implemented over a four year period starting in 2006.
NEC's first submarine cable earthquake observation system was constructed off the east coast of Japan in 1979. Since then, NEC has planned, built and deployed earthquake and tsunami observation cable systems throughout nine adjoining areas. These durable systems continue to reliably provide valuable information for observation centers based on land.
Looking forward, NEC aims to capitalize on these accomplishments and know-how in order to expand into new regions and to contribute to earthquake and environmental observations on a worldwide scale.