... sustainability seamount deep-sea seamount seafloor geology modeling observation geologist strength social responsibility sediment plume tide technology amplitude cobalt-rich crust mining geophysical research social impact assessment environmental impact assessment crust mining...

... to improve equipment maintenance and operation during deployment. INTRODUCTION Polymetallic nodules (also referred to as manganese nodules or nodules) on the seafloor are spherical to ellipsoidal manganese-oxide concretions ranging from a few to 10 cm in diameter. They contain metals such as copper...

... japan government metals & mining seafloor asia government rock model data mining crc deep seafloor dredged rock height adjustment system reservoir characterization cutter head excavation substrate cobalt mining mining testing machine adjustment system commercial development...

... Abstract This paper reviews and discusses some important design and position-control parameters and issues of the deep seafloor nodule collector-miners of a few consortia, including the subsystems that the international consortia had developed since the 1970s. It includes the OMCO's full-scale...

... measurement point numerical simulation seafloor virtual point lower panel contribution thermal water arsenic concentration Numerical Analysis of Arsenic Concentration in the Marine Sediments of Bagnoli Bay Mohammad Daliri a, Renato Somma b, c, Mariano Buccino a, Claudia Troise b, Flavia Molisso d...

... Recently, developments in submarine-based mining have actively increased throughout the world. Submarine-based mining may negatively affect the surrounding ecosystem and environments as it results in seafloor disturbance, subsequent suspension, diffusion of sediment particles, and redeposition (Furuuchi et...

... for depths up to 30–60 m above the seafloor. A numerical model indicated that a suitable environment for ADCP measurement is formed mainly by the bottom mixed layer. Additionally, at some measurement sites a fluctuation was observed in the depth range of successful measurements. This fluctuation may be due...

... by Japan coastal wave observation network (NOWPHAS). Then, by comparing NOWPHAS and in-situ observation, we verify whether NOWPHAS data can represent the wave condition at the construction site. submerged cooling water outlet scour protection simulation seafloor us government water management...

...) on the caisson soil reaction are investigated with the undrained soil behavior simulated using a Mohr-Coulomb constitutive model. soil reaction caisson penetation seafloor circumferential soil friction wall surface suction caisson padeye 180 caisson soil reaction behavior xiaoyan sealoo downward...

... or pressure changes, the pore pressure increases associated with volume expansion of the gas released during gas hydrate dissociation will likely result in fractures filled with pressurized fluid products open accompanied by softening of soil in gas and water intrusion zone together with seafloor...

... Abstract Our prototype of a 3000-m-class underwater glider for long-term virtual mooring will rise and descend between the seafloor and the sea surface periodically to monitor the sea environment over one year. It can sleep on the seafloor to extend the operation period. To evaluate its pitch...

... characteristic hydraulic conductivity bsf reservoir characterization penetration preconsolidation pressure deepwater sediment seafloor deposit Geological and Geotechnical Characteristics of Deepwater Sediments in Offshore Japan Xiaoyan Long, Ko Min Tjok, Aurelian C. Trandafir, Fugro GeoConsulting, Inc...

... Abstract An Offshore Wind Tower (OWT) supported by a bottom-supported jacket can become uneconomical due to several reasons including larger turbines, an increase in water depth, and very poor foundation material. An OWT-supported by a floating structure tethered to the seafloor is an obvious...

... A Numerical Model Analysis of Environmental Load for Seafloor Resources Development Joji Yamamoto1, Hideyuki Oka2, Yasuharu Nakajima1, Shotaro Uto3and Sotaro Masamobu1 1Ocean Engineering Department, National Maritime Research Institute. Mitaka, Tokyo, Japan 2Maritime Risk Assessment Department...

... caissons in the South China Sea in 1970. Recent events have revived an interest in dry-tree drilling. deep water structural concept floating production system bullwinkle subsea system dry tree well spar fpso dry tree drilling compliant tower tether seafloor drilling riser upstream oil...

... deck wellbay and seafloor. There are also constraints on the deck spacing and the riser offset at seafloor relative to the wellbay location, i.e. riser vertical angle. For fields with substantial reserve, the number of TTRs may become large; and thus the TTRs may cluster together, which makes the riser...

.... Rubble mound structures and vertical curtain-walled bodies submerged in the sea have been adopted for generating upwelling currents from the seafloor. The purpose of this study is to find out the most effective seafloor mounted structure for developing the upwelling current in comparatively deep seas...

... ABSTRACT Japan Agency for Marine-Earth Science and Technology (JAMSTEC) has developed the working AVU MR-X1 in order to conduct light work such as setting/collecting instruments that are placed in the seafloor autonomously. And now, it is also used as the testbed to apply new advanced technologies...

... rock core inner core tube upstream oil & gas mechanism umbilical cable deployment seafloor drilling operation drilling head cylinder underwater battery seafloor shallow-hole multi-coring drill subsystem drilling tool hydraulic system inner core tube changing hydraulic motor...

... ABSTRACT There are chemosynthetic ecosystems nearby deep-sea mineral and energy resources such as seafloor massive sulfides and methane hydrate. A prediction model that predicts the response of the ecosystems due to changes in environmental condition should be developed to assess the impact...