The technique of ocean bottom cable (OBC) dual-sensor acquisition is an effective method to suppress the ghost wave and the reverberation at the receiver. With the advent of this technique, the processing method has b...The technique of ocean bottom cable (OBC) dual-sensor acquisition is an effective method to suppress the ghost wave and the reverberation at the receiver. With the advent of this technique, the processing method has become the key to the effective use of the OBC dual-sensor data. This paper has developed a new set of processing workflow based on the principle of combining the hydrophone and geophone data. This new process was applied to the OBC data acquired in Bohai area. The actual processing results show that the ghost and the reverberation are attenuated effectively. The frequency energy of the first notch point of the hydrophone data increased from −22 dB to −13 dB, and the frequency energy of the first notch point of the geophone data increased from −18 dB to −10 dB. The spectral characteristics of the dual-sensor data are more reasonable. The frequency spectrum is broadened and richer, and the resolution of the stack profile is improved greatly.展开更多
A cabled ocean observatory system that can provide abundant power and broad bandwidth communication for undersea instruments is developed. A 10 kV direct current （kVDC） with up to 10 kW power, along with l Gigabit/s...A cabled ocean observatory system that can provide abundant power and broad bandwidth communication for undersea instruments is developed. A 10 kV direct current （kVDC） with up to 10 kW power, along with l Gigabit/sec Ethemet communication, can be transmitted from the shore to the seafloor through an umbilical armored cable. A subsea junction box is fixed at a cable terminal, enabling the extension of up to nine connections. The box consists of three main pressure vessels that perform power conversion, power distribution, and real-time communication functions. A method of stacking modules is used to design the power conversion system in order to reduce the 10 kV voltage to levels that can power the attached instruments. A power distribution system and an Ethemet communication system are introduced to control the power supply and transmit data or commands between the terminals and the shore station, respectively. Specific validations of all sections were qualified in a laboratory environment prior to the sea trial. The ocean observatory system was then deployed at the coast of the East China Sea along with three in situ instruments for a 14-day test. The results show that this high voltage-powered observatory system is effective for subsea long-term and real-time observations.展开更多
文摘The technique of ocean bottom cable (OBC) dual-sensor acquisition is an effective method to suppress the ghost wave and the reverberation at the receiver. With the advent of this technique, the processing method has become the key to the effective use of the OBC dual-sensor data. This paper has developed a new set of processing workflow based on the principle of combining the hydrophone and geophone data. This new process was applied to the OBC data acquired in Bohai area. The actual processing results show that the ghost and the reverberation are attenuated effectively. The frequency energy of the first notch point of the hydrophone data increased from −22 dB to −13 dB, and the frequency energy of the first notch point of the geophone data increased from −18 dB to −10 dB. The spectral characteristics of the dual-sensor data are more reasonable. The frequency spectrum is broadened and richer, and the resolution of the stack profile is improved greatly.
基金supported by the National High-Technology Research and Development Program of China(Grant No.2007AA091201-1)
文摘A cabled ocean observatory system that can provide abundant power and broad bandwidth communication for undersea instruments is developed. A 10 kV direct current （kVDC） with up to 10 kW power, along with l Gigabit/sec Ethemet communication, can be transmitted from the shore to the seafloor through an umbilical armored cable. A subsea junction box is fixed at a cable terminal, enabling the extension of up to nine connections. The box consists of three main pressure vessels that perform power conversion, power distribution, and real-time communication functions. A method of stacking modules is used to design the power conversion system in order to reduce the 10 kV voltage to levels that can power the attached instruments. A power distribution system and an Ethemet communication system are introduced to control the power supply and transmit data or commands between the terminals and the shore station, respectively. Specific validations of all sections were qualified in a laboratory environment prior to the sea trial. The ocean observatory system was then deployed at the coast of the East China Sea along with three in situ instruments for a 14-day test. The results show that this high voltage-powered observatory system is effective for subsea long-term and real-time observations.
