数字式主动声呐研制的初步探索     

许鹭芬  毛岱山 《台湾海峡》2005,24(4):463-468

首先介绍数字式主动声呐的优点及实现上的特殊困难．采用时间相关积累信号处理方法，可以克服海洋背景噪声和船只自噪声的干扰，并具有强烈的抗起伏性能．在垂直向下探测或短距离、高频探测等特殊条件下，依混响的衰减规律，由微机组成精确的灵敏度时间控制网络，可以抑制混响的影响，并大大地简化了目标识别的难题．回声测深仪、垂直探鱼仪及本文介绍的浅海航行暗礁障碍探测仪的研制和海上实验，说明了这个结论．  相似文献   

海底三维可视化技术及应用   总被引：1，自引：1，他引：1  

李军  滕惠忠 《海洋测绘》2004,24(4):44-47

海底地形地貌能表现海洋世界重要的空间信息，也是常规光学和电磁手段难以探测的水下区域。应用侧扫声纳技术可以反演海底地貌，同时多波束测深技术得到的水深数据重建数字水深模型，二者结合创建三维海底空间景观。利用海洋探测技术和三维可视化技术进行海底地形地貌三维仿真和分析，并对其应用进行探讨。  相似文献   

Contribution of the multibeam acoustic imagery to the exploration of the sea-bottom   总被引：1，自引：0，他引：1  

J. M. Augustin  R. Le Suave  X. Lurton  M. Voisset  S. Dugelay  C. Satra 《Marine Geophysical Researches》1996,18(2-4):459-486

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Geometric corrections on sidescan sonar images based on bathymetry. Application with SeaMARC II and Sea Beam data     

Pierre Cervenka  Christian De Moustier  Peter F. Lonsdale 《Marine Geophysical Researches》1994,16(5):365-383

Acoustic backscatter images of the seafloor obtained with sidescan sonar systems are displayed most often using a flat bottom assumption. Whenever this assumption is not valid, pixels are mapped incorrectly in the image frame, yielding distorted representations of the seafloor. Here, such distortions are corrected by using an appropriate representation of the relief, as measured by the sonar that collected the acoustic backscatter information. In addition, all spatial filtering operations required in the pixel relocation process take the sonar geometry into account. Examples of the process are provided by data collected in the Northeastern Pacific over Fieberling Guyot with the SeaMARC II bathymetric sidescan sonar system and the Sea Beam multibeam echo-sounder. The nearly complete (90%) Sea Beam bathymetry coverage of the Guyot serves as a reference to quantify the distortions found in the backscatter images and to evaluate the accuracy of the corrections performed with SeaMARC II bathymetry. As a byproduct, the processed SeaMARC II bathymetry and the Sea Beam bathymetry adapted to the SeaMARC II sonar geometry exhibit a 35m mean-square difference over the entire area surveyed.On leave at the Naval Research Laboratory, Code 7420, Washington D.C. 20375-5350.  相似文献   

现代长江口水下底坡上的微地貌类型及分区     

陈卫民  杨作升  曹立华  郭志刚  刘浩  杜静萍 《中国海洋大学学报(自然科学版)》1993,(Z1)

旁侧扫描声纳记录真实地揭示出现代长江口水下底坡上发育的微地貌形态。指出微地貌的形态特征及其分布规律与长江泥沙的传输分布、长江口区海域的水动力机制密切相关。  相似文献   

Processing Multibeam Backscatter Data   总被引：1，自引：0，他引：1  

Qiu-hua Tang  Xing-hua Zhou  Zhong-chen Liu  De-wen DU 《Marine Geodesy》2005,28(3):251-258

A new highly precise source of data has recently become available using multibeam sonar systems in hydrography. Multibeam sonar systems can provide hydrographic quality depth data as well as high-resolution seafloor sonar images. We utilize the seafloor backscatter strength data of each beam from multibeam sonar and the automatic classification technology so that we can get the seafloor type identification maps. In this article, analyzing all kinds of error effects in backscatter strength, data are based on the relationship between backscatter strength and seafloor types. We emphasize particularly analyzing the influences of local bottom slope and near nadir reflection in backscatter strength data. We also give the correction algorithms and results of these two influent factors. After processing the raw backscatter strength data and correcting error effects, we can get processed backscatter strength data which reflect the features of seafloor types only. Applying the processed backscatter strength data and mosaicked seafloor sonar images, we engage in seafloor classification and geomorphy interpretation in future research.  相似文献   

Recording the migration behaviour of fish schools by multi-beam sonar during conventional acoustic surveys     

Hafsteinsson  M. T.; Misund  O. A. 《ICES Journal of Marine Science》1995,52(6):915-924

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Progressive deformation of an evaporite-bearing accretionary complex: SeaMARC I,SeaBeam and piston-core observations from the Mediterranean Ridge     

Kim A. Kastens  Nancy A. Breen  Maria B. Cita 《Marine Geophysical Researches》1992,14(4):249-298

The Mediterranean Ridge is an arcuate ridge of deformed sediment caught up in the convergent plate margin between the African plate and the Aegean. An intensive campaign of SeaMARC I and SeaBeam surveys followed by piston coring has been conducted along the contact between undeformed turbidites of the Sirte Abyssal Plain and folded and faulted sediments of the Mediterranean Ridge. Along the outer edge of the Ridge, surficial sediments have been deformed into sinusoidal ridges and troughs (wavelengths 0.5–2 km, amplitude 20–150 m), which we interpret as folds. In plan view, the ridge and the trough fabric parallels the NW-SE trending regional contours, suggesting that the folds formed in response to compression orthogonal to the Mediterranean Ridge. The outermost ridge is shedding a debris apron out onto the abyssal plain, implying that uplift and deformation are ongoing. We show that the geometry of the outermost folds can be produced by elastic bending of a packet of 5–10 relatively strong layers, each 10–20 m thick, interbedded between weaker layers; we equate the strong layers with gypsum beds in the Messinian upper evaporites. Folding the seafloor from a flat layer into the observed ridge and trough topography would shorten the layer by less than 2%. Two percent shortening (equals two percent thickening) is insufficient to create the observed relief of the Mediterranean Ridge even if the entire sediment column down to basement were involved; we infer that additional shortening/thickening is accommodated by thrust faulting above a decollement at the top of the Messinian salt layer. At distances > 15 km from the deformation front and more than 500 m from the abyssal plain, sharp-edged, fine-grained side-scan lineations with very little vertical relief cut across the kilometer-scale ridge and trough topography. These fine-grained lineations fall in two groups trending N/S to NNE/SSW and ~ENE. We interpret these lineaments as traces of conjugate strike-slip faults formed in the same compressional regime which formed the NW/SE trending folds. The onset of strike-slip faulting may coincide with the cessation of imbricate thrust fan development above the initial salt-controlled decollement surface. The following characteristics of the Mediterranean Ridge are attributed to the presence of evaporites in the incoming sedimentary section: (1) initial deformation by folding rather than thrust faulting; (2) narrow taper; (3) rapid rate of outward growth; (4) karstification.  相似文献   

侧扫声纳系统及其在海洋环境监测和保护中的应用   总被引：3，自引：0，他引：3  

鱼京善  成二丽 《海洋测绘》2004,24(2):63-66

总结了侧扫声纳系统在海洋环境监测和保护中的应用，介绍了侧扫声纳基本工作原理及其发展情况，并且对其以后的发展进行了简单探讨。  相似文献   

莺歌海盆地中央坳陷带海底天然气渗漏系统初探   总被引：1，自引：2，他引：1       下载免费PDF全文

李列  宋海斌  杨计海 《地球物理学进展》2006,21(4):1244-1247

地球物理资料表明，莺歌海盆地区麻坑众多，浅层气发育，在高分辨率地震剖面上可以识别出到达海底的地震模糊带，在3.5 kHz的浅层剖面上可见穿透到海底的气体聚集带，在声呐图像可以识别出麻坑.莺歌海盆地不仅在其边缘隆起带沉积层较薄的地区存在海底天然气渗漏现象，而且在中央坳陷带沉积层巨厚的地区也存在海底天然气渗漏，海底天然气渗漏在莺歌海盆地是广泛分布的.莺歌海盆地广泛分布的海底天然气渗漏是全球海底天然气渗漏系统的重要组成部分，海底天然气渗漏系统排出的大量甲烷气体的一部分可能穿越水层到达海面.  相似文献