11:45 〜 12:00
[HSC06-11] 社会的受容を目指したCCSモニタリングにおける小型震源装置の震源波形への音楽の利用
キーワード：CCS、音楽、相互相関、震源波形、小型震源装置
This study investigates the potential use of music as a source function for a small seismic source in CO2 sequestration monitoring, with the aim of increasing public acceptance. In conventional offshore CCS monitoring, large seismic sources such as airguns are commonly used. However, their impact on fish and marine mammals, as well as concerns about social acceptability, have been identified as significant issues. Meanwhile, seismic surveys using small seismic sources have been developed as an alternative approach. However, their emitted waveforms typically consist of chirp signals, that can cause discomfort. Despite these advances, research into a more socially acceptable source function is still lacking.
This study investigated music as a socially acceptable sound and analyzed its effect on signal transmission to assess the feasibility of using music as a source function. The main analysis methods used were cross-correlation and stacking. Experiments were conducted for both onshore and offshore CCS scenarios, with two trials in each setting using a small seismic source. Different pieces of music were used as source functions and their characteristics were analyzed in relation to signal transmission performance.
The experimental results showed that in the offshore trials, pipe organ music produced clearer low-frequency body waves than chirp signals. In addition, certain pieces of music were found to contribute to an increased propagation distance of surface waves. Five key characteristics of music suitable for use as a source function were also identified:
(1) Sufficient energy in the low frequency range below 100 Hz.
(2) Uniform amplitude distribution in both frequency and time domain.
(3) Recording of live instrumental performances rather than synthetic or mechanically generated sounds.
(4) Low proportion of rhythmic components in the low frequency range.
(5) Short duration notes with minimal sustained tones.
These findings suggest that by selecting music that meets these criteria, it is possible to use music as a source function.
This study investigated music as a socially acceptable sound and analyzed its effect on signal transmission to assess the feasibility of using music as a source function. The main analysis methods used were cross-correlation and stacking. Experiments were conducted for both onshore and offshore CCS scenarios, with two trials in each setting using a small seismic source. Different pieces of music were used as source functions and their characteristics were analyzed in relation to signal transmission performance.
The experimental results showed that in the offshore trials, pipe organ music produced clearer low-frequency body waves than chirp signals. In addition, certain pieces of music were found to contribute to an increased propagation distance of surface waves. Five key characteristics of music suitable for use as a source function were also identified:
(1) Sufficient energy in the low frequency range below 100 Hz.
(2) Uniform amplitude distribution in both frequency and time domain.
(3) Recording of live instrumental performances rather than synthetic or mechanically generated sounds.
(4) Low proportion of rhythmic components in the low frequency range.
(5) Short duration notes with minimal sustained tones.
These findings suggest that by selecting music that meets these criteria, it is possible to use music as a source function.