南海トラフ
In addition to the national R&amp;D research program, there have been cruise expeditions carried out at drill observation wells in the Nankai Trough region by the Integrated Ocean Drilling Program (IODP) and its forerunner, the Ocean Drilling Program (ODP), to analyze the geochemical composition of the gas and to collect geological and geophysical data on the reservoir units. In 2010 and 2011, extensive research was completed on seven expeditions (314, 315, 316: first stage; 319 and 322: second stage; 326, 332 and 333: third stage) in order to complete three Nankai Trough Seismogenic Zone Experiments (NanTroSEIZE), which are expected to give groundbreaking new insights on the seismology and geophysical conditions of the area. NanTroSeize aims to drill, sample, and instrument the earthquake causing, seismogenic active portion of Earth’s crust, where large-scale earthquakes have occurred repeatedly throughout history, also influencing the gas hydrate deposits.