【作者】 孙革；

【导师】 翟世奎；

【作者基本信息】 中国海洋大学 ， 海洋地质， 2007， 博士

【摘要】 本文从国家专项课题“西北太平洋海底环境调查”的子专题“EW(Q)区块多波束海底地形调查”的科学需求出发,以多波束测深理论为依托,从声速校正方法的理论研究到基于各种方法的仿真实验,从东海沙脊区声速剖面特性分析到其对测深的影响,将声速校正方法理论研究的成果应用到东海沙脊区多波束调查的数据处理中,从理论到实践完成了多波束测深系统声速校正方法研究及其在东海沙脊区海底地形校正中的应用。声速剖面精度及其校正方法直接影响多波束测深数据的精度,其主要原因是由于环境参数直接影响着声线折射弯曲程度。因此,针对不同的海区环境,实时对多波束测深系统的声线进行跟踪,选取或建立针对调查区的校正方法,以提高测量精度成为目前多波束勘测工作中的研究热点。本文主要从数据后处理方面,对多波束测深系统声线弯曲的改正方法加以研究,其结果在选择的目标调查区得到了很好的应用。本文在分析了声速结构对声线弯曲影响的基础上,提出了要对实际现场测量的声速剖面进行仔细研究分析,选取相应的措施或技术方法对原始勘测资料进行处理,以提高多波束声线弯曲修正精度;通过统计分析现有的5种声速经验公式得出了适合不同水层的最优声速公式,其成果在浅水区被验证是正确的,具有推广使用的可能性;建立了在深度方向上采用声线跟踪技术进行声速补偿,以提高深度测量精度的技术方法,给出了利用现场测得的声速——深度分布曲线进行声线跟踪的数学模型;利用所给的声线跟踪技术进行声速补偿,可以大大提高海底深度和对应海底点位置测量的精度;考虑到声线跟踪法的缺陷,论证并提出了等效声速剖面法声线改正模型,给出了声线改正方法的计算过程,并对其优缺点进行了系统的分析;根据国家专项EW区块多波束调查结果,进行了资料精细后处理。重点针对调查区声速剖面时空结构的特点,分别采用声线跟踪技术和等效声速剖面法对实测多波束水深数据进行了声速校正处理,最大限度地减小了因为声速剖面的多变性带来的测量误差值。更多还原

【Abstract】 Starting from scientific requirement of the sub-subject (multi-beam bathymetric survey on EW(Q) zone) of the national specialized project, known as“survey on the northwest pacific ocean bottom”, the author has completed all the work from theoretical research on the method of sound velocity correction to the simulations based on various methods, from analyzing the characteristics of sound velocity profile of the sand ridge in the eastern sea to its influence on bathymetric. By applying the algorithms of sound velocity correction to the data processing in the multi-beam survey, research on the method of sound velocity correction and its application in correcting seabed topographic characteristics of the sand ridge area in the eastern sea are completed.Since environment factors influence the bend of sound ray directly, the accuracy of sound velocity profile and its correction algorithm will affect multi-beam bathymetric accuracy. How to track sound ray of the multi-beam bathymetric in real-time and establish correction methods for different environment have become a hot pursuit in multi-beam bathymetric. Mainly from the point of data processing, research on how to correct the bend of sound ray is carried out, application results show that it has good quality.Based on the analysis on how various sound velocity structure affect the bend of sound ray, the author proposes that sound velocity profile measured on the spot should be carefully analyzed, and corresponding measures and techniques be applied to process the original acquired data, in order to improve the correction accuracy of bend of sound ray. Based on the statistics induced by the analysis of the current sound velocity classical formulas, an optimized formula fit for different water depth will be acquired. Experiments in shallow water prove the formula is right and possess the possibility of practical application. An depth-oriented acoustic ray tracking technique used to supplement the acoustic velocity has been worked out to improve the depth measuring precision. In light of the relationship between the sound velocity and depth demonstrated by the distribution curve, a methmatics model to track sound ray is built. The precision of sea-bed depth and corresponding postion measuring can be greatly improved by applying the sound ray tracking technique. Considering the defects of sound ray tracking technique, an adjusted model of equivalent sound velocity profile technique is proposed. The computing procedure for adjusting the sound velocity is presented, the advantages and disadvantages of which also are analyzed. Based on the results of the survey on multi-beam in EW(Q) zone, the corrected materials get processed. Focusing on the characteristics of the time-space construction of survey area, the sound ray tracking and equivalent sound profile techniques are respectively adopted to correct the sound velocity data acquired through on spot multi-beam measuring, which greatly reduces the measuring error.更多还原