The development of long-term borehole observation systems in IODP and their role in earthquake monitoring

Abstract:

Ocean drilling has been carried out for more than 50 years. Not only have a large number of cores been drilled to promote the progress of Earth Science， but also the application of long-term borehole observation systems has provided valuable data for multidisciplinary research. This paper comprehensively reviews various long-term borehole observation systems since the implementation of ocean drilling， and focuses on analyzing the structures and installation details of the Smart Plug and the Genius Plug micro-observation systems and the LTBMS long-term observation system equipped on the Japanese “Chikyu” drilling ship. These systems can capture storm， tsunami and earthquake signals， and the networked data of LTBMS also reveals the correlation between pore pressure changes and crustal deformation. For example， by analyzing the temperature and pressure data monitored by the Smart Plug， the relationship between transient pressure and earthquakes and tsunamis can be studied； by comparing the pressure data of different systems， it can be determined whether the crust has deformed； and by synthesizing the data of multiple networked borehole observation systems， it is helpful to explore the earthquake nucleation mechanism. Deeply exploring the functions of these systems and the practical experience of Japan has important implications for the research and development of related systems in China， and is of great significance for a deeper understanding of the tectonic evolution of the earth and the laws of earthquake activities.