含水合物松散沉积物声速剖面成像技术研究  

Study of the Technology to Obtain the Sound Velocity Profile of Hydrate Bearing Unconsolidated Sediments

作　　者：方跃龙 胡高伟[2,3] 刘昌岭[2,3] 赵仕俊[1,4] 

机构地区：[1]中国石油大学(华东)信息与控制工程学院,山东青岛266555 [2]国土资源部天然气水合物重点实验室,山东青岛266071 [3]青岛海洋地质研究所,山东青岛266071 [4]中国石油大学(华东)石油仪器仪表研究所,山东东营257061

出　　处：《新能源进展》2015年第4期309-318,共10页Advances in New and Renewable Energy

基　　金：国家自然科学基金(41104086)

摘　　要：本文基于射线理论的超声层析成像技术,采用自适应消噪技术除去天然气水合物(NGH)实验模型固有噪声,运用直射线追踪法和基于联合迭代重建算法(Simultaneous Iterative Reconstruction Techniques,SIRT)的迭代重建法实现超声层析成像的正演和反演,针对水合物实验获取的波形,得到NGH在松散沉积物中形成时的地层声速剖面结构图像。结果表明,使用超声层析成像技术获取的含NGH沉积物的二维声速剖面结构能够准确反应不同时刻沉积物中NGH饱和度及分布情况,并且纵横波速度剖面结构的变化趋势大体相同。同时本文也结合常用的NGH声速预测模型,针对实验数据,对声速与NGH饱和度之间的关系进行了讨论。According to the ultrasonic tomography technology based on ray theory, the adaptive noise cancellation was adopted to remove the premise of autoclave under the inherent noise. The straight ray-tracing method and the iterative algorithm based on SIRT algorithm were applied to realize forward modeling and inversion of the ultrasonic tomography. Then the acoustic velocity profile distribution images of hydrate formation in loose sediments were obtained. The results showed that the two-dimensional sound velocity profile structures of hydrate bearing sediments obtained by using ultrasonic tomography technology could accurately reflect the distribution of hydrate in sediments at different time and saturation. The P-wave velocity profile structures fit in well with S-wave velocity profile structures. Besides, with the experimental data, several velocity models were used to validate the relationship between the sonic velocity and the saturation of hydrate.

关 键 词：天然气水合物 声学速度剖面 自适应消噪 层析成像 超声波换能器 

分 类 号：TK01[动力工程及工程热物理]