17:15 〜 19:15
[SCG55-P09] Hybrid Dive Operations Using the Human-Occupied Vehicle Shinkai 6500 and Analysis of Sunken Woods
キーワード：しんかい6500、音響探査、サイドスキャンソーナー、沈木、CTスキャン、蛍光X線分析
The Human-Occupied Vehicle (HOV) Shinkai 6500 enables us direct visual observation of the seafloor, taking high-resolution photography, and precise sample collection. Over the years, she has established significant contributions to various fields of deep-sea research.
In recent years, we developed the integrated system of acoustic survey capabilities as a payload on Shinkai 6500, allowing simultaneous seafloor and sub-seafloor surveys combining with direct observation and sampling, in one dive operation [1] [2]. In 2024, as part of the Strategic Innovation Promotion (SIP) program [3], the latest acoustic equipment such as interferometric (IF) sonar for bathymetry and side-scan sonar (SSS) image, sub-bottom profiler (SBP) for shallow sub-surface layer image, and high accuracy doppler velocity log (DVL) was carefully installed on the vehicle as a payload instrument. The acquired data were displayed on a laptop PC brought to the vehicle to operate and synchronize the equipment, the observer could easily detect any anomalies in real time. Precise coordinates of the vehicle were also distributed to all acoustic data in real time, which were calculated using the DVL, bathymetric map with visualized anomalies were provided immediately. This is the most helpful information for the observer to prioritize the locations where to observe “in the vehicle, at the site”. This technological advancement has further enhanced the hybrid dive operations of Shinkai 6500.
During a test dive conducted in a bay to evaluate this new survey system, side-scan sonar detected anomalies at three locations on the seafloor. Then the vehicle descended to the coordinates indicated by the sonar imagery and conducted detailed observations, revealing that the anomalies were composed of sunken wood and rock deposits.
To determine the nature of these materials, some pieces of the sunken wood were collected and subjected to computed tomography scanning, X-ray fluorescence analysis, and radiocarbon (C14) dating after the cruise.
In this presentation, we report a summary of the hybrid dive operations conducted with Shinkai 6500 and the findings of the collected samples.
References:
[1] Machida et al. (2019) The 126th Annual Meeting of the Geological Society of Japan.
[2] Kaneko et al. (2022) OCEANS 2022 Chennai.
[3] https://www.jamstec.go.jp/sip3/e/ National Platform for Innovative Ocean Developments
In recent years, we developed the integrated system of acoustic survey capabilities as a payload on Shinkai 6500, allowing simultaneous seafloor and sub-seafloor surveys combining with direct observation and sampling, in one dive operation [1] [2]. In 2024, as part of the Strategic Innovation Promotion (SIP) program [3], the latest acoustic equipment such as interferometric (IF) sonar for bathymetry and side-scan sonar (SSS) image, sub-bottom profiler (SBP) for shallow sub-surface layer image, and high accuracy doppler velocity log (DVL) was carefully installed on the vehicle as a payload instrument. The acquired data were displayed on a laptop PC brought to the vehicle to operate and synchronize the equipment, the observer could easily detect any anomalies in real time. Precise coordinates of the vehicle were also distributed to all acoustic data in real time, which were calculated using the DVL, bathymetric map with visualized anomalies were provided immediately. This is the most helpful information for the observer to prioritize the locations where to observe “in the vehicle, at the site”. This technological advancement has further enhanced the hybrid dive operations of Shinkai 6500.
During a test dive conducted in a bay to evaluate this new survey system, side-scan sonar detected anomalies at three locations on the seafloor. Then the vehicle descended to the coordinates indicated by the sonar imagery and conducted detailed observations, revealing that the anomalies were composed of sunken wood and rock deposits.
To determine the nature of these materials, some pieces of the sunken wood were collected and subjected to computed tomography scanning, X-ray fluorescence analysis, and radiocarbon (C14) dating after the cruise.
In this presentation, we report a summary of the hybrid dive operations conducted with Shinkai 6500 and the findings of the collected samples.
References:
[1] Machida et al. (2019) The 126th Annual Meeting of the Geological Society of Japan.
[2] Kaneko et al. (2022) OCEANS 2022 Chennai.
[3] https://www.jamstec.go.jp/sip3/e/ National Platform for Innovative Ocean Developments