合成孔径声纳技术在海底管道探测中的应用进展     

于灏  王培刚  段康弘  张小波 《海洋测绘》2015,35(3):20-23

从合成孔径声纳的基本原理、研究进展、应用,以及实际应用中存在的问题等几个方面,探讨了该技术在海底管道探测方面的应用潜力。国内外一些海域开展的探索性应用显示,该技术可以对海底管道的埋设状态及其周边海域地形地貌和其他小目标清晰成像,并且能够获得管道状态和位置等的细节信息。然而,鉴于海洋水声环境的复杂性和特殊性,SAS在实际应用中仍存在一些问题,需要在信号处理方法、作业方式等方面进行更为深入的研究探索。  相似文献   

Target-strength estimates of schooling herring and mackerel using the comparison method   总被引：1，自引：0，他引：1  

Misund  Ole Arve; Beltestad  Arvid K. 《ICES Journal of Marine Science》1996,53(2):281-284

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侧扫声纳系统成图中的位移、变形和噪声问题   总被引：1，自引：0，他引：1  

高俊国  李增林  杜军 《海岸工程》2003,22(2):44-50

侧扫声纳声图判读的正确性和准确性对海洋工程的实施和维护中具有非常重要的作用。但诸多影响因素的存在使得声纳声图不能真实反映海底状况。了解这些因素，并在判读过程中尽可能消除其影响，以达到正确和准确判读是非常有意义的。本文将这些影响因素按照作用结果分为位移、变形和噪声3个大类，并对其校正或消除方法进行讨论。  相似文献   

Spatial variability of bottom types in the lower Chesapeake Bay and adjoining estuaries and inner shelf     

L. D. Wright  D. B. Prior  C. H. Hobbs  R. J. Byrne  J. D. Boon  L. C. Schaffner  M. O. Green 《Estuarine, Coastal and Shelf Science》1987,24(6)

The spatial distributions of the bed textural and morphologic properties that influence boundary-layer roughness characteristics in the lower Chesapeake Bay, the lower portions of the York, James and Elizabeth Rivers, and the adjacent inner continental shelf were systematically mapped. A high resolution, fully-corrected side-scan sonar mapping system (100 kHz) was used for remote acoustic detection of bottom roughness, supported by ‘ground-truthing’ by direct in situ observations by divers. These complementary methods proved to be especially effective in detecting a wide range of roughness-controlling bed surface properties at various scales. Fine-scale variations in sediment size and associated bottom texture are considered to be the main source of heterogeneity in Nikuradse (skin friction) roughness. A wide variety of small- and intermediate-scale morphologic elements provide meso-scale and small-scale distributed (form drag) roughness. Depending upon location, the distributed roughness may be either biogenic or hydrodynamically induced (by currents and waves), although anthropogenic roughness prevails in certain instances (e.g. port areas). In terms of particular combinations of roughness scales and types, combined sonar and diver observation data allow the beds to be systematically but qualitatively classified into 10 bottom types, each of which is associated with a particular type of subenvironment.  相似文献   

Extensional faulting and segmentation of the Mid-Atlantic Ridge north of the Kane Fracture Zone (24° 00′ N to 24° 40′ N)     

Simon Allerton  Bramley J. Murton  Roger C. Searle  Malcolm Jones 《Marine Geophysical Researches》1995,17(1):37-61

The combination of multi-beam echo-sounder swath bathymetry and high-resolution deep-towed sidescan sonar provides a powerful database from which to examine mid-ocean ridge processes. We have used such a database, gathered from the Mid-Atlantic Ridge north of the Kane Fracture Zone (the MARNOK area), to examine the relationship between tectonic, volcanic, and bathymetric segmentation. We have identified structural domains, with different fault distributions, and neovolcanic segments that are distinct from the 2nd or 3rd order bathymetric segmentation.From their mutual relationships, a model is proposed for the magmatic accretion of oceanic crust at slow spreading ridges that relates the local melt supply to the tectonic style. We suggest that these are mutually interactive, and determine whether volcanic extrusion along the ridge is continuous and slow, or episodic and rapid.  相似文献   

Possibilities of using the GLORIA system for manganese nodule assessment   总被引：1，自引：0，他引：1  

Q. J. Huggett  M. L. Somers 《Marine Geophysical Researches》1988,9(3):255-264

The I.O.S. long range side-scan sonar GLORIA has been widely used over a variety of seabed types, but until recently had not been used over an independently authenticated field of manganese nodules. In the Eastern Atlantic Ocean at approximately 31°25 N 25°15 W, a field of nodules approximately 3–6 cm in diameter covering up to 18% of the seafloor was observed using an underwater camera. The nodule field occurred over approximately 2.8 km of the 8.3 km camera run. The corresponding GLORIA image shows an area of medium intensity backscattering, approximately 3.7 km in diameter. Considering the likely contrast in acoustic reflectivity between manganese nodules and deep sea sediments, we propose a correlation between the nodules observed in the photographs and the medium intensity echo target revealed by the GLORIA system.  相似文献   

Behaviour of mackerel schools during summer feeding migration in the Norwegian Sea, as observed from fishing vessel sonars   总被引：1，自引：0，他引：1  

Godo  Olav Rune; Hjellvik  Vidar; Iversen  Svein A.; Slotte  Aril; Tenningen  Eirik; Torkelsen  Terje 《ICES Journal of Marine Science》2004,61(7):1093-1099

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Tectonic evolution of Gorda Ridge inferred from sidescan sonar images     

D. G. Masson  D. A. Cacchione  D. E. Drake 《Marine Geophysical Researches》1988,10(3-4):191-204

Gorda Ridge is the southern segment of the Juan de Fuca Ridge complex, in the north-east Pacific. Along-strike spreading-rate variation on Gorda Ridge and deformation of Gorda Plate are evidence for compression between the Pacific and Gorda Plates. GLORIA sidescan sonographs allow the spreading fabric associated with Gorda Ridge to be mapped in detail. Between 5 and 2 Ma, a pair of propagating rifts re-orientated the northern segment of Gorda Ridge by about 10° clockwise, accommodating a clockwise shift in Pacific-Juan de Fuca plate motion that occurred around 5 Ma. Deformation of Gorda Plate, associated with southward decreasing spreading rates along southern Gorda Ridge, is accommodated by a combination of clockwise rotation of Gorda Plate crust, coupled with left-lateral motion on the original normal faults of the ocean crust. Segments of Gorda Plate which have rotated by different amounts are separated by narrow deformation zones across which sharp changes in ocean fabric trend are seen. Although minor lateral movement may occur on these NW to WNW structures, no major right-lateral movement, as predicted by previous models, is observed.  相似文献   

Improving the quantitative estimation of trawling impacts from sidescan-sonar and underwater-video imagery     

Smith  C. J.; Banks  A. C.; Papadopoulou  K-N. 《ICES Journal of Marine Science》2007,64(9):1692-1701

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Accuracy of the spatial representation of the seafloor with bathymetric sidescan sonars     

Pierre Cervenka  Ute Christina Herzfeld  Christian De Moustier 《Marine Geophysical Researches》1994,16(6):407-425

When isobath maps of the seafloor are constructed with a bathymetric sidescan sonar system the position of each sounding is derived from estimates of range and elevation. The location of each pixel forming the acoustic backscatter image is calculated from the same estimates. The accuracy of the resulting maps depends on the acoustic array geometry, on the performances of the acoustic signal processing, and on knowledge of other parameters including: the platform's navigation, the sonar transducer's attitude, and the sound rays' trajectory between the sonar and the seafloor. The relative importance of these factors in the estimation of target location is assesed. The effects of the platform motions (e.g. roll, pitch, yaw, sway, surge and heave) and of the uncertainties in the elevation angle measurements are analyzed in detail. The variances associated with the representation (orientation and depth) of a plane, rectangular patch of the seafloor are evaluated, depending on the geometry of the patch. The inverse problem is addressed. Its solution gives the lateral dimensions of the spatial filter that must be applied to the bathymetric data to obtain specified accuracies of the slopes and depths. The uncertainty in the estimate of elevation angle, mostly due to the acoustic noise, is found to bring the main error contribution in across-track slope estimates. It can also be critical for along-track slope estimates, overshadowing error contributions due to the platform's attitude. Numerical examples are presented.On leave at the Naval Research Laboratory, Code 7420, Washington D.C. 20375-5350, U.S.A.  相似文献