由于水底和水面的影响,结构在有限水深环境中的辐射声场与在自由空间中的辐射声场有很大区别。为了更高效准确地分析有限水深环境中大规模结构的辐射声场,文章构建一种快速边界元法(boundary element method,BEM)。采用宽频快速多极算...由于水底和水面的影响,结构在有限水深环境中的辐射声场与在自由空间中的辐射声场有很大区别。为了更高效准确地分析有限水深环境中大规模结构的辐射声场,文章构建一种快速边界元法(boundary element method,BEM)。采用宽频快速多极算法对计算过程进行加速处理,针对算法中最为耗时的M2L/F2H变换过程,通过建立判定准则将均匀层格林函数中的多阶虚源分为近场和远场,从而设计不同求解方案,极大减少M2L/F2H的变换次数,显著提高求解效率。数值算例验证了文章方法的准确性和高效性,并体现出该方法在浅海声学分析中的工程潜力。展开更多
Few seismic exploration work was carried out in Tibetan Plateau due to the characteristics of alpine hypoxia and harsh environmental protection needs.Complex near surface geological conditions,especially the signal sh...Few seismic exploration work was carried out in Tibetan Plateau due to the characteristics of alpine hypoxia and harsh environmental protection needs.Complex near surface geological conditions,especially the signal shielding and static correction of permafrost make the quality of seismic data is not ideal,the signal to noise ratio(SNR)is low,and deep target horizon imaging is difficult.These data cannot provide high quality information for oil and gas geological survey and structural sedimentary research in the area.To solve the issue of seismic exploration in Tibetan Plateau,this test used low frequency vibroseis wide-line and high-density acquisition scheme.In view of the actual situation of the study area,the terrain,the source and the diff erent observation system were simulated,and the processing technique was adopted to improve the quality of seismic data.Low-frequency components with a minimum of 1.5Hz of vibroseis ensure the deep geological target imaging quality in the area,the seismic profi le wave group is clear,and the SNR is relatively high,which can meet the needs of oil and gas exploration.Seismic data can provide the support for the development of oil and gas survey in the Tibet plateau.展开更多
文摘由于水底和水面的影响,结构在有限水深环境中的辐射声场与在自由空间中的辐射声场有很大区别。为了更高效准确地分析有限水深环境中大规模结构的辐射声场,文章构建一种快速边界元法(boundary element method,BEM)。采用宽频快速多极算法对计算过程进行加速处理,针对算法中最为耗时的M2L/F2H变换过程,通过建立判定准则将均匀层格林函数中的多阶虚源分为近场和远场,从而设计不同求解方案,极大减少M2L/F2H的变换次数,显著提高求解效率。数值算例验证了文章方法的准确性和高效性,并体现出该方法在浅海声学分析中的工程潜力。
基金This work was supported by Nation key R&D program(No.2016YFC060110305)Geological and mineral investigation and evaluation special project(No.DD20160160 and No.DD20160181).
文摘Few seismic exploration work was carried out in Tibetan Plateau due to the characteristics of alpine hypoxia and harsh environmental protection needs.Complex near surface geological conditions,especially the signal shielding and static correction of permafrost make the quality of seismic data is not ideal,the signal to noise ratio(SNR)is low,and deep target horizon imaging is difficult.These data cannot provide high quality information for oil and gas geological survey and structural sedimentary research in the area.To solve the issue of seismic exploration in Tibetan Plateau,this test used low frequency vibroseis wide-line and high-density acquisition scheme.In view of the actual situation of the study area,the terrain,the source and the diff erent observation system were simulated,and the processing technique was adopted to improve the quality of seismic data.Low-frequency components with a minimum of 1.5Hz of vibroseis ensure the deep geological target imaging quality in the area,the seismic profi le wave group is clear,and the SNR is relatively high,which can meet the needs of oil and gas exploration.Seismic data can provide the support for the development of oil and gas survey in the Tibet plateau.
