HR: 1340h
AN: OS43B-0550 [Abstracts]
TI: 10 Year Video Monitoring and its Implication to the Fluctuation Detected by Multi-disciplinary
Observation on Deep Seafloor at Cold Seepage Site in Sagami Bay, Central Japan
AU: * Iwase, R
EM: iwaser@jamstec.go.jp
AF: JAMSTEC, 3173-25 Showa-machi, Kanazawa-ku, Yokohama, Kanagawa, 236-0001
Japan
AB:
As a part of multidisciplinary real-time observation at cold seepage site on deep seafloor which faces swarm earthquake area
at a depth of 1175 m off Hatsushima Island in Sagami Bay, central Japan, video monitoring has been carried out for about 10
years by a cabled observatory. Through the monitoring, both outbreak event such as mudflows caused by earthquakes and
long-term phenomena such as sedimentation on seafloor associated not only with mudflow but also with the fluctuation of the
amount of suspended particles were observed, along with spawning of clams or other biological events. Some of these video
images provide important information on the fluctuation observed by other sensors of the observatory, such as seasonal
changes in sub-bottom temperature and intensity of gamma-ray, indicating that those fluctuations were primarily related to
such environmental changes on seafloor as sedimentation. On the other hand, extracting meaningful events or phenomena from a
huge amount of stored video images needs tremendous time and effort. Effective methodology of scene detection and indexing is
necessary to be developed.
UR: http://www.jamstec.go.jp/REMOTE/hatsushima/
DE: 3015 Heat flow (benthic) and hydrothermal processes
DE: 3022 Marine sediments--processes and transport
DE: 3045 Seafloor morphology and bottom photography
DE: 3094 Instruments and techniques
SC: Ocean Sciences [OS]
MN: 2004 AGU Fall Meeting