In studies on gas hydrate,bottom-simulating reflectors(BSR)are used to determine the potential hydrate-bearing sedimentary layers.Usually,BSR detection is performed manually by experienced interpreters.Therefore,a met...In studies on gas hydrate,bottom-simulating reflectors(BSR)are used to determine the potential hydrate-bearing sedimentary layers.Usually,BSR detection is performed manually by experienced interpreters.Therefore,a method for implementing an auto-matic BSR detection process should be established.In this study,we develop a novel architecture for BSR characterization using the convolutional neural network(CNN)technique.We propose the use of Stokes’transform(ST)to obtain a time-frequency spectrum for the input of CNN.ST fully uses the frequency content of the seismic data,and a part of the 3D seismic data collected from the Blake Ridge is utilized to train the CNN.Synthetic seismic records with variable signal-to-noise ratios(SNR),as well as Blake Ridge seismic data,were used to validate the detection effect of the CNN.Results show that the CNN trained by this method exhibits excellent performance in noise-resistant testing and achieves an accuracy of more than 89% in field seismic data detection.展开更多
The biological removal of CH4 by methanotrophic(CH4-oxidizing)archaea always occurs at a distinct zone which is known as sulfate-methane transition zone(SMTZ).It is an important indication for high methane flux and ga...The biological removal of CH4 by methanotrophic(CH4-oxidizing)archaea always occurs at a distinct zone which is known as sulfate-methane transition zone(SMTZ).It is an important indication for high methane flux and gas hydrate occurrence.In this study,we collected pore-water data from South China Sea,Carolina Rise and Blake Ridge to analyze the relationship between CH4,SO42−concentration and depth.We found that below the SMTZ,the methane concentration increases continuously with depth and sulfate concentration decrease linearly to zero.In addition,the geochemical data taken from all these sites show that SMTZ is relatively shallow(less than 20 m),which may indicate that these areas have high methane flux.展开更多
基金supported by the Fundamental Research Funds for the Central Universities(No.202262012)the National Natural Science Foundation of China(No.42076224)the National Key R&D Program of China(No.2021YFC2801200).
文摘In studies on gas hydrate,bottom-simulating reflectors(BSR)are used to determine the potential hydrate-bearing sedimentary layers.Usually,BSR detection is performed manually by experienced interpreters.Therefore,a method for implementing an auto-matic BSR detection process should be established.In this study,we develop a novel architecture for BSR characterization using the convolutional neural network(CNN)technique.We propose the use of Stokes’transform(ST)to obtain a time-frequency spectrum for the input of CNN.ST fully uses the frequency content of the seismic data,and a part of the 3D seismic data collected from the Blake Ridge is utilized to train the CNN.Synthetic seismic records with variable signal-to-noise ratios(SNR),as well as Blake Ridge seismic data,were used to validate the detection effect of the CNN.Results show that the CNN trained by this method exhibits excellent performance in noise-resistant testing and achieves an accuracy of more than 89% in field seismic data detection.
基金the Key Geological Issues in China Sea,the China Geological Survey(Nos.DD20160147 and GZH201100202)the Taishan Scholar Project Grant to Guangxue Li.
文摘The biological removal of CH4 by methanotrophic(CH4-oxidizing)archaea always occurs at a distinct zone which is known as sulfate-methane transition zone(SMTZ).It is an important indication for high methane flux and gas hydrate occurrence.In this study,we collected pore-water data from South China Sea,Carolina Rise and Blake Ridge to analyze the relationship between CH4,SO42−concentration and depth.We found that below the SMTZ,the methane concentration increases continuously with depth and sulfate concentration decrease linearly to zero.In addition,the geochemical data taken from all these sites show that SMTZ is relatively shallow(less than 20 m),which may indicate that these areas have high methane flux.
