九龙江口北岸的叠置贝壳堤与晚全新世的海面波动     

郑晓云 《海洋科学》1990,14(3):17-21

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地层学的发展推动油气地质理论研究的进步   总被引：2，自引：0，他引：2  

许红  李思田  吴河勇 《海洋地质前沿》2002,18(2):17-21

自上个世纪50年代以来,地层学经历了彻底的变革,逐渐由“相模式”、“沉积体系”、“地震地层学”发展到目前的“层序地层学”,形成高分辨率层序地层学和事件地层学的理论体系和研究方法。文章围绕层序地层学、高分辨率层序地层学基本方法及理论体系,与含油气系统相关关系进行了讨论。  相似文献   

海洋天然气水合物调查地震采集技术——调查初始阶段研究   总被引：1，自引：0，他引：1  

伍忠良  曾宪军  王立明 《海洋技术学报》2006,25(4):79-87

地震调查方法在水合物中的应用分为两个主要阶段:调查初始阶段和调查深入阶段。调查初始阶段以“突出天然气水合物的四大主要识别标志(似海底反射、振幅空白带、穿层特征、振幅和速度结构异常)”为主要目的,为资料的处理、解释提供丰富的地震信息。从而圈定天然气水合物富集程度高、成藏条件好的“目标”靶区,开展深入调查,更好地展现“天然气水合物矿体立体上的形态特征”,了解“水合物矿体的厚度、顶底界面及富集程度”。文中从震源技术研究、高分辨率地震调查技术的调谐组合参数研究和野外施工方法等方面的内容出发,根据大量野外技术试验资料和有关科研成果,总结了在天然气水合物调查初始阶段的特点及相应的地震调查技术。  相似文献   

Crustal Structures of the Northernmost South China Sea: Seismic Reflection and Gravity Modeling   总被引：2，自引：0，他引：2  

Yi-Ching Yeh  Shu-Kun Hsu 《Marine Geophysical Researches》2004,25(1-2):45-61

The South China Sea (SCS) is a marginal sea off shore Southeast Asia. Based on magnetic study, oceanic crust has been suggested in the northernmost SCS. However, the crustal structure of the northernmost SCS was poorly known. To elaborate the crustal structures in the northernmost SCS and off southwest Taiwan, we have analyzed 20 multi-channel seismic profiles of the region. We have also performed gravity modeling to understand the Moho depth variation. The volcanic basement deepens southeastwards while the Moho depth shoals southeastwards. Except for the continental margin, the northernmost SCS can be divided into three tectonic regions: the disturbed and undisturbed oceanic crust (8–12 km thick) in the southwest, a trapped oceanic crust (8 km thick) between the Luzon-Ryukyu Transform Plate Boundary (LRTPB) and Formosa Canyon, and the area to the north of the Formosa Canyon which has the thickest sediments. Instead of faulting, the sediments across the LRTPB have only displayed differential subsidence offset of about 0.5–1 s in the northeast side, indicating that the LRTPB is no longer active. The gravity modeling has shown a relatively thin crust beneath the LRTPB, demonstrating the sheared zone character along the LRTPB. However, probably because of post-spreading volcanism, only the transtension-shearing phenomenon of volcanic basement in the northwest and southeast ends of the LRTPB can be observed. These two basement-fractured sites coincide with low gravity anomalies. Intensive erosion has prevailed over the whole channel of the Formosa Canyon.  相似文献   

透射射线的非线性效应     

夏冬明  王修田  蒋卫焱 《中国海洋大学学报(自然科学版)》2006,36(5):705-708

根据Snell定律提出了透射射线的非线性效应的概念,从理论上证明了当地震射线的轨迹在1个界面上为1条直线时在另1个界面上可为1条曲线;并进一步通过射线追踪实验证明:当地下介质为非水平层状介质时,即使对应于地面同一条直线段上的接收点,来自地下同一个界面上的反射点的轨迹仍可为一条曲线。  相似文献   

An Application of Direct Ritz Method for Random Seismic Responses of Jacket Platforms     

韩晓双马骏  赵德有周波 《中国海洋工程》2006,20(4):673-679

1 .IntroductionNowadays tremendous efforts have been devotedtothe analysis of randomseismic responses .Forexample ,American PetroleumInstitute (API) has declared that the analysis of randomseismic re-sponsesis a useful tool for safety inspection. Owing to the complexity of platformand randomness ofload,it is difficult to carry out the randomresponse analysis of a jacket platform. The conventionalrandomvibration methods ,such as square root of the sumof squares (SRSS) and complete quadratic…  相似文献   

Comparison among four kinds of data of sea surface wind stress in the South China Sea   总被引：1，自引：0，他引：1  

Xie Qiang  Wang Weiqiang  Mao Qingwen 《海洋学报(英文版)》2002,21(2):263-273

By using remote sensing (ERS) data, FSU data, COADS data and Hellerman & Rosen-stein objective analysis data to analyze the sea surface wind stress in the South China Sea, it is found that the remote sensing data have higher resolution and more reasonable values. Therefore we suggest that remote sensing data be chosen in the study of climatological features of sea surface wind stress and its seasonal variability in the South China Sea, especially in the study of small and middle scale eddies.  相似文献   

Prediction of Load Carrying Capacity of Corroded Reinforced Concrete Beam     

范颖芳  周晶冯新 《中国海洋工程》2004,18(1):107-118

A novel method for prediction of the load carrying capacity of a corroded reinforced concrete beam (CRCB) is presented in the paper. Nine reinforced concrete beams, which had been working in an aggressive environment for more than 10 years, were tested in the laboratory. Comprehensive tests, including flexural test, strength test for corroded concrete and rusty rebar, and pullout test for bond strength between concrete and rebar, were condueted. The flexural test results of CRCBs reveal that the distribution of surface cracks on the beams shows a fractal behavior. The relationship between the fractal dimensions and mechanical properties of CRCBs is then studied. A prediction model based on artificial neural network (ANN) is established by the use of the fractal dimension as the corrosion index, together with the basic intbrmation of the beam. The validity of the prediction model is demonstrated through the experimental data, and satisfactory resuits are achieved.  相似文献   

半封闭海湾潮间带部分围垦后纳潮量计算的商榷——以胶州湾为例   总被引：14，自引：1，他引：14  

杨世伦  陈启明  朱骏  张经 《海洋科学》2003,27(8):43-47

传统的海湾(泻湖)纳潮量计算方法不能精确地反映潮间带被部分围垦后纳潮量的实际情况,本考虑围堤的影响,将纳潮量分解为堤基以下的“梯形”区和堤基以上的“矩形”区两部分之和,在理论上更加严密。根据改进后方法算出的胶州湾近期纳潮量比传统方法算出的纳潮量大15％左右。可见,半个多世纪以来胶州湾的纳潮量只减少了约15％．而不是传统方法得出的约25％。  相似文献   

Modelling nitrogen and phosphorus cycles and dissolved oxygen in the Zhujiang Estuary Ⅰ.Model results     

管卫兵  王丽娅  许东峰 《海洋学报(英文版)》2001,(4)

rmIoxThe averag annual dischaIge of the Zhujiang Xiver is 3. 32 x l0ll m3, which ranks theZhujiang River just end to the Changjiang River in China. The dischnye occutring duringthe fltal m between APril and ffepteTnber accounts for 80% of the yearly total. The Zhu-jiang hiver has a yeaIy sediment load of about 1 x l08 tons, which also concentrates in theM arn (Zhao, l990; Chen et al., 1998). The Zhujiang Xiver delta,which has l2 cities ofdifferent sizes and more than 40 towns with a po…  相似文献