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机载LiDAR测深技术被认为是海洋测绘领域极具潜力的对地观测新技术,国内对LiDAR测深的试验大都是针对南海这类水质较清的区域。本研究首次在国内引入先进的CZMIL(Coastal Zone Mapping and Imaging LiDAR)系统,选取较为浑浊的江苏省骆马湖作为试验测区,进行了测深试验。试验结果表明,在测区有着低底部反射率、高漫衰减系数的情况下,CZMIL系统仍能够成功探测到湖底数据,成果精度达到了CZMIL系统标称的测深精度指标,具有较好测深探测能力和精度。 相似文献
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多波束测深系统采用条带测量方式,可对水底进行全覆盖无遗漏测量,具有高精度、高效率、高质量等优点。本文概述了EM1002型多波束测深系统的技术性能,详细介绍了运用Calibrate多参数校准软件对其内部参数的校正。 相似文献
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On the basis of the data of sounding performed in the deep-water part of the sea down to 1920 m (for a depth of the sea of 2000 m), we study specific features of the vertical distribution of the beam attenuation coefficient in the violet (418 nm) and red (659 nm) spectral bands through the entire thickness of the hydrogen-sulfide zone including the bottom hydrologically homogeneous layer of water. The data of optical measurements performed in the bottom layer for the first time demonstrate that this layer is also optically uniform. 相似文献
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Soundings on nautical charts provide information about the shape of the ocean bottom between chart depth curves. A single chart may have thousands of soundings posted on it. This article describes a system for automatic cartographic sounding selection. In this system, a new algorithm for automated selecting soundings is developed. The algorithm is employed in such a way that it can guarantee (a) fast and accurate selecting sounding, (b) processing the circular depth curves, (c) solving the overplotting problems between depth curves and soundings, and (d) keeping selected soundings “prettier.” The system was intensively tested using real data sets, and its superiority has been revealed by the testing results. 相似文献
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Soundings on nautical charts provide information about the shape of the ocean bottom between chart depth curves. A single chart may have thousands of soundings posted on it. This article describes a system for automatic cartographic sounding selection. In this system, a new algorithm for automated selecting soundings is developed. The algorithm is employed in such a way that it can guarantee (a) fast and accurate selecting sounding, (b) processing the circular depth curves, (c) solving the overplotting problems between depth curves and soundings, and (d) keeping selected soundings “prettier.” The system was intensively tested using real data sets, and its superiority has been revealed by the testing results. 相似文献
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In order to enhance the efficiency of the interpretation of surface images obtained with a side scanning sonar, it is proposed to supplement the standard processing software with a program for obtaining acoustic stereo images. Examples of such images synthesized with this program using the data of a bottom sonar survey with a side scanning sonar and an echo sounder are presented. The cases are considered when the information on the bottom relief contained in sonar images obtained with a standard side scanning sonar or its modifications can be used instead of the data of an echo sounding survey. 相似文献
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A. A. Ostrovsky 《Marine Geophysical Researches》1989,11(2):113-118
The results of the study of short impulsive signals (microshocks) which constitute a specific type of noise on the records of ocean bottom seismographs are given. Various possible causes of their origin have been analysed. It is shown that the great majority of microshocks are produced by external causes: bottom displacements under an instrument at the deployment site and the mechanical action of marine organisms on OBSs. To cope with this kind of noise the use of parallel recording at two seismometers some distance apart is suggested. 相似文献
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An active source electromagnetic sounding system for marine use 总被引：2，自引：0，他引：2
M. C. Sinha P. D. Patel M. J. Unsworth T. R. E. Owen M. R. G. Maccormack 《Marine Geophysical Researches》1990,12(1-2):59-68
Instrumentation has been developed for carrying out active source electromagnetic sounding experiments in the deep oceans. Experiments of this type are directly and uniquely sensitive to the presence of molten or partially molten material, to temperature structure and to the porosity of upper crustal rocks such as those that accommodate hydrothermal circulation systems. Electromagnetic sounding experiments therefore represent an extremely desirable addition to the existing range of geophysical techniques for studying geological processes in thermally, hydrothermally or magmatically active regions—for example, at oceanic spreading centres.The instruments can be operated in regions of rugged, unsedimented sea bottom terrain, and are designed for investigating the distribution of electrical conductivity within the oceanic crust and uppermost mantle. The instrumentation consists of a deep towed, horizontal electric dipole transmitter and a set of free-fall, sea bottom, horizontal electric field recording devices.The transmitter is a deep-towed instrument, which is provided with power from the towing ship through a conducting cable. The transmitter package is fitted with an integral echo sounder, which allows it to be towed safely a short distance above the seabed. Electromagnetic signals are transmitted from a neutrally-buoyant antenna array, which is streamed behind the deep tow.The sea bottom receiving instruments each consist of a recoverable package which contains the instrumentation and digital recording system, an acoustic release unit, four low-noise, porous electrodes arranged in two orthogonal, horizontal dipoles, and a disposable bottom weight.The instruments have been used at sea on three occasions. On their most recent use, active source signals were successfully recorded during an experiment to investigate crustal magmatism and hydrothermal circulation beneath the axis of the East Pacific Rise. 相似文献
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The CTD and nephelometric sounding data are considered along with the parameters of the nearbottom currents and particulate fluxes measured by a subsurface mooring station in the northern part of the Bear Island Trough. It is shown that the near-bottom current is characterized by highly variable parameters, while the distribution of suspended particulate matter demonstrates surface and bottom maximums. The horizontal and vertical fluxes of sedimentary matter in the nepheloid layer are studied. 相似文献
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A computer code that simulates multibeam echo‐sounding over realistic (three‐dimensional) bathymetry was used to compare available sounding systems. Two‐dimensional modeling dealt with the resolution of seafloor bathymetry and with the effect of postprocessing algorithms for some typical multibeam systems. The 2‐D bathymetric inputs were idealized bottom features. Three‐dimensional modeling dealt with the gross character of the seafloor, as detected by echo‐sounding systems. The 3‐D bathymetric inputs were realizations of terrain generated by a stochastic model of seafloor roughness. Three‐dimensional modeling indicated that the sounding system may slightly shift the location of peaks within the beam footprint. In addition, the simulated measurements were more sensitive to low‐wavenumber features (i.e., large‐scale roughness) than to high‐wavenumber features (i.e., small‐scale roughness). Resolution gradually decreased with increasing distance from centerline, due to the increasing footprint size of beams at increasing angular distance from the vertical. Lineated terrain was also smoothed by simulated echo‐sounding; lineations may indeed remain undetected if sounding system parameters are not properly selected. Inversion of the simulated measurements indicated that echo‐sounding measurements are dependent not only on the characteristics of the sounding system itself, but on other factors such as the character of the roughness and the orientation of the survey relative to the strike of lineations. The modeling technique provides a way to quantify the system response of a multibeam echo‐sounding system. This work resulted in recommendations as to the most appropriate system for an application in an area of rough bathymetry, and it led to the establishment of criteria for comparing multibeam systems in future applications. 相似文献
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A “Pingerprobe” is a system of echo sounding in which the sound source is placed near bottom to improve resolution by restricting the area investigated. It is demonstrated that a commercially available 12-kHz “pinger” with a synchronized shipboard receiver is useful not only in the monitoring of the positioning of a bottom or near-bottom instrument package (such as a corer) but also in making observations on the acoustic nature of the sea floor. In rough terrain the Pingerprobe has measured stratified sediments in some places where the PDR (Precision Depth Recorder) cannot. Observations on proximal abyssal plains indicate that the prolonged echo character common to these areas may result from small-scale roughness or inhomogeneity. When a suspended instrument is sent to the bottom in rough terrain, or in areas of intermittent subbottom reflections, use of a Pingerprobe improves information about the conditions at the point of contact and permits selection of the desired topographic setting. 相似文献
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Regional deep seismic sounding—refracted wave seismic profiles across the Sea of Azov, the Caspian, and the Black seas carried out by the Shirshov Institute of Oceanology, Russian Academy of Sciences, in 1957–2002 with the use ocean bottom seismographs—provided information on the deep structure of the regions studied. Multichannel seismic profiling helped to refine the structure of the sedimentary cover. A combined interpretation of the reflection and refraction data allowed us to construct structural-lithological models of the southern seas of Russia and to estimate their oil and gas potential. 相似文献
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Frederick K. Duennebier Grant Blackinton George H. Sutton 《Marine Geophysical Researches》1981,5(1):109-115
High-amplitude, anrrow band noise that correlates with periods of high ocean bottom currents and the tidal cycle is occasionally observed on ocean bottom seismometers (OBS). The geophones on OBSs of different configurations are not equally sensitive to this noise and hydrophones are almost unaffected. With a suitable design, it should be possible to eliminate this noise problem.Hawaii Institute of Geophysics Contribution No. 1173 相似文献
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Depth dependence of noise resulting from ship traffic and wind 总被引：1，自引：0，他引：1
Under conditions of distantly generated noise, the noise level is found to decrease with depth in the mid-northeastern Pacific. These data show a decrease in noise level greater than 25 dB between critical depth and the ocean bottom. A result of this decrease is that locally wind-generated noise can be detected on near-bottom receivers for wind speeds less than 10 kn. It is shown that the noise level generated form local sources such as wind and nearby shipping is almost independent of receiver depth. The differences in spectra shape between the distant shipping noise and wind-generated noise and the low noise levels detected near the ocean bottom allow the measurement in the frequency band at 200-500 Hz of local wind noise level for wind speeds less than 10 kn 相似文献
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I. P. Chunchuzov V. G. Perepelkin O. E. Popov S. N. Kulichkov A. A. Vardanyan G. Y. Ayvazyan Kh. Z. Khachikyan 《Izvestiya Atmospheric and Oceanic Physics》2017,53(3):279-293
Results of acoustic sounding of the lower troposphere with the aid of detonation generators of acoustic pulses are given. This sounding method is based on a partial reflection of acoustic pulses with shock fronts from vertical wind-velocity and temperature gradients continuously varying with height in the troposphere and on the penetration of reflected signals into the region of acoustic shadow. Experiments on tropospheric sounding were carried out on the ground of the Barva Innovation Scientific and Technical Center (Talin, Armenia) in September 2015. In these experiments, an antihail acoustic system was first used as a generator of acoustic pulses. Experimental results have been compared with data obtained earlier in similar experiments carried out in the vicinity of Zvenigorod with the use of a special detonation generator of acoustic pulses. Due to the high resolution (in height) of the sounding method, which reaches 1 m in the stably stratified lower troposphere within a height range of 250–600 m, the vertical profiles of layered effective sound speed inhomogeneities with vertical scales from a few to a few tens of meters have been retrieved. The influence of these fluctuations on the form and amplitude of acoustic signals at a long distance from their pulsed source has been studied. 相似文献
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利用最小二乘向量机(LS-SVM)算法构造海底趋势面的过程中,由于算法解缺乏稀疏性,使得异常测深训练样本对最终构造的函数模型也产生影响。为了解决该问题,在对留一样本交叉检核法研究的基础上提出了LS-SVM稀疏算法,由于留一样本交叉检核法求解的残差序列可以有效地表示函数预测值偏离实际水深的程度,因此利用该原则重新修剪后的样本数据不仅使算法具有稀疏特性,而且构造的函数模型更合理。为了检验算法的有效性,选取实测的多波束测深数据进行验证,计算结果表明留一样本交叉检核法能够合理地筛选出对函数模型构造贡献程度大的测深训练样本,使得构造的函数模型更合理。 相似文献