A new hybrid pressure-coring system for the drilling vessel Chikyu

Abstract. Retrieving core samples without releasing the in situ hydrostatic pressure during core recovery is one of the many technical challenges in scientific drilling. We report here a newly developed hybrid pressure-coring system for the use on the drilling vessel Chikyu and its successful use during expeditions 906 and 802 in the Nankai Trough of Japan. The system is gas-tight and hence enables researchers to study in situ geophysical and geochemical characteristics of sediments containing gaseous components, such as methane hydrates that cannot be reliably recovered with nonpressure coring systems. In addition, pressure coring is a powerful tool, not only for scientific but also for hydrocarbon resources research.