Assessment of Offshore New Jersey Sources of Beach Replenishment Sand by Diversified Application of Geologic and Geophysical Methods

Beach replenishment serves the dual purpose of maintaining a source of tourism and recreation while protecting life and property. For New Jersey, sources for beach sand supply are increasingly found offshore. To meet present and future needs, geologic and geophysical techniques can be used to improve the identification, volume estimation, and determination of suitability, thereby making the mining and manag ing of this resource more effective. Current research has improved both data collection and interpretation of seismic surveys and vibracore analysis for projects investigating sand ridges offshore of New Jersey. The New Jersey Geological Survey in cooperation with Rutgers University is evaluating the capabilities of digital seismic data (in addition to analog data) to analyze sand ridges. The printing density of analog systems limits the dynamic range to about 24 dB. Digital acquisition systems with dynamic ranges above 100 dB can permit enhanced seismic profiles by trace static correction, deconvolution, automatic gain scaling, horizontal stacking and digital filtering. Problems common to analog data, such as wave-motion effects of surface sources, water-bottom reverberation, and bubble-pulse-width can be addressed by processing. More than 160 line miles of digital high-resolution continuous profiling seismic data have been collected at sand ridges off Avalon, Beach Haven, and Barnegat Inlet. Digital multichannel data collection has recently been employed to map sand resources within the Port of New York New Jersey expanded dredge-spoil site located 3 mi offshore of Sandy Hook, New Jersey. Multichannel data processing can reduce multiples, improve signal-to-noise calculations, enable source deconvolution, and generate sediment acoustic velocities and acoustic impedance analysis. Synthetic seismograms based on empirical relationships among grain size distribution, density, and velocity from vibracores are used to calculate proxy values for density and velocity. The seismograms are then correlated to the digital seismic profile to confirm reflected events. They are particularly useful where individual reflection events cannot be detected but a waveform generated by several thin lithologic units can be recognized. Progress in application of geologic and geophysical methods provides advan tages in detailed sediment analysis and volumetric estimation of offshore sand ridges. New techniques for current and ongoing beach replenishment projects not only expand our knowledge of the geologic processes involved in sand ridge origin and development, but also improve our assessment of these valuable resources. These reconnaissance studies provide extensive data to the engineer regarding the suitability and quantity of sand and can optimize placement and analysis of vibracore samples.     

滨海砂土对可溶性油的吸附作用和影响因素研究

在现场自然地理、水文地质条件调查的基础上,对青岛海水浴场采集砂和海水样品进行主要物理化学性质分析,探讨吸附机理的影响因素,通过吸附试验建立砂样对可溶性油吸附的动力学方程和吸附等温线,经过批量试验确定温度、盐度和pH值对吸附量的影响。研究结果表明,砂土对可溶性油吸附的平衡吸附量为90~110 mg/kg,吸附平衡时间为14~16 h,符合Henry型直线等温物理吸附。对等温式进一步分析发现,当水相中可溶性油浓度低于一定数值时,不但不产生吸附,反而会使污染沙滩上的残留油分释放出来,造成二次污染。     

新型海上静力触探设备的研制与应用

海上静力触探是一种操作简单、经济高效、测量数据可靠的海床土体原位测量方法。国内自主研发的海上静力触探设备很少能够广泛的应用在实际工程勘察中。本文介绍了一种新型海上静力触探设备,由贯入系统、液压系统、甲板控制系统、浮力系统四部分组成,可在地形复杂多样的滩浅海区域进行连续走航测试。利用这套设备在黄河口海域进行地质勘察,并对该海域的海床土层结构划分进行了探讨,证明了该设备在滩浅海地区的工程勘察领域有者广阔的应用前景。     

An Engineering Application Tool for Visual Assessment of the Equilibrium Beach

An engineering application tool for prediction of the static equilibrium bay(Beach Mod)is established to describe two bay shape formulas by use of the programming software "MATLAB" with a graphic user interface(GUI).The tool is user-friendly for engineering students for the design of beach shapes.This tool was tested through application on three types of beaches in Taiwan and Australia.By implementing the concept of Headland Control,the Beach Mod program allows users to draw a structure and create an artificial headland.The results indicate that Beach Mod can efficiently forecast beach changes as well as MEPBAY,a competing software package,while boasting a better user interface.     

Use of Federal Sand for Beach Nourishment and Shore Protection Projects

Coastal shoreline protection and beach nourishment are significant issues for coastal states along the Atlantic and Gulf coasts. In some areas, there is a critical need to identify suitable sources of sand for possible use in public works projects for coastal protection. The continental shelf contains large resources of sand and gravel that could be used to support such projects. The U.S. Department of the Interior's (DOI) Minerals Management Service (MMS) provides policy direction and guidance for development of the resources located on the federal portion of the continental shelf. This article highlights the MMS's Sand Program, focusing on its cooperative resource and environmental studies with several coastal states, significant milestones and accomplishments, and anticipated activities in 1998 and beyond. Management of sand resources on the federal portion of the continental shelf has been made easier by a federal state partnership concept. Using this cooperative concept, joint projects are being conducted to investigate offshore sand resources, potential sites, extraction methods, and related environmental conditions. The MMS has procedures for negotiating sand agreements under the Outer Continental Shelf Lands Act (OCSLA) and ensuring that the resources are developed in an environ mentally sound manner. The authority to negotiate with project sponsors, an important recent change in the OCSLA, also resides with the MMS. This 1992 change in OCSLA facilitates the use of Outer Continental Shelf (OCS)resources for public projects. Further, the MMS is authorized to assess a fee based on the value of the resource and the public interest served. The MMS has worked with local sponsors and authorized the use of OCS sand for two projects. However, additional resource and environmental projects, as well as negotiated agreements, are anticipated within the near future with states and local governments along the Atlantic and Gulf coasts.     

Life Histories and Breeding Patterns of Three Intertidal Sand Beach Isopods

Abstract. Three-weekly transects were done over a 14-month period at Sundays River Beach, a high energy beach in Algoa Bay, South Africa, to determine the life histories, breeding patterns, and fecundities of three intertidal cirolanid isopods. Eurydice longicornis. Pontogeloides latipes , and Excirolana naialensis. E. longicornis exhibits an annual, multivoltine life history with a more extended breeding period than the other two species. P. latipes and E. natalensis both have biennial. univoltine life histories with lower fecundities than E. longicornis.     

Use of Federal Sand for Beach Nourishment and Shore Protection Projects

Coastal shoreline protection and beach nourishment are significant issues for coastal states along the Atlantic and Gulf coasts. In some areas, there is a critical need to identify suitable sources of sand for possible use in public works projects for coastal protection. The continental shelf contains large resources of sand and gravel that could be used to support such projects. The U.S. Department of the Interior's (DOI) Minerals Management Service (MMS) provides policy direction and guidance for development of the resources located on the federal portion of the continental shelf. This article highlights the MMS's Sand Program, focusing on its cooperative resource and environmental studies with several coastal states, significant milestones and accomplishments, and anticipated activities in 1998 and beyond. Management of sand resources on the federal portion of the continental shelf has been made easier by a federal state partnership concept. Using this cooperative concept, joint projects are being conducted to investigate offshore sand resources, potential sites, extraction methods, and related environmental conditions. The MMS has procedures for negotiating sand agreements under the Outer Continental Shelf Lands Act (OCSLA) and ensuring that the resources are developed in an environ mentally sound manner. The authority to negotiate with project sponsors, an important recent change in the OCSLA, also resides with the MMS. This 1992 change in OCSLA facilitates the use of Outer Continental Shelf (OCS)resources for public projects. Further, the MMS is authorized to assess a fee based on the value of the resource and the public interest served. The MMS has worked with local sponsors and authorized the use of OCS sand for two projects. However, additional resource and environmental projects, as well as negotiated agreements, are anticipated within the near future with states and local governments along the Atlantic and Gulf coasts.     

荷兰人工育滩工程Sand Motor的经验与启示

海岸侵蚀已成为砂质海岸重要灾害之一,世界各国都致力于海滩防护。荷兰由于地势低洼,在护滩工程中进行大量尝试,于2011年在代尔夫兰海岸开展创新性人工育滩工程即Sand Motor,单个工程补沙总量达2.15×107 m3。持续监测结果显示,工程建成后的沙滩形态与模拟结果基本吻合,沙量损失速度低于预期。阶段性评价结果表明,Sand Motor通过波浪、海流等向海滩缓慢输沙,稳定海岸沙滩和海岸沙丘,具有防护效果显著、成本较低、使用寿命长、增加海岸利用等优点,值得我国借鉴。     

一种新型的海上锚固设施--火箭锚的作用机理及应用

介绍了一种新型的锚固设施——火箭锚,对其作用机理进行了探讨,同时还介绍了火箭锚的构造和布设方法,阐述了火箭锚在不同工程领域的应用前景．     

大港湾海域环境质量现状评价与分析

根据2009年8月对大港湾海域的水质、沉积物、生物监测结果,采用环境质量单项评价标准指数法,根据海洋环境功能区划对该海域环境质量现状进行了评价与分析;并综合分析了水质中富营养化程度,沉积物中重金属的富集程度及潜在生态风险指数。     

山东省海砂砾石资源潜力及开发利用前景

山东省是一个海域辽阔、岸线漫长且近海海砂砾石资源较丰富的省份,近海海砂砾石不仅类型多,而且资源量大,将是山东省矿产资源利用的一个重要的新领域,具有广阔的开发利用前景.开展海砂、砾石资源开发利用前景评价工作,系统地安排浅海砂砾石资源的勘查评价工作具有重要意义.     

System Reliability Analysis of Offshore Strctures and Component Safety Rank Assessment

Offshore structures will encounter serious environmental load,so it is important to study thestructural system reliability and to evaluate the structural component safety rank.In this paper,thebracnch-and-bound method is adopted to search the main failure path,and the Ditlevsen bound method isused to calculate the system failure probability.The structure is then assessed by the fuzzy comprehensiveassessment method,which evaluates the structural component safety rank.The ultimate equation of the tu-bular cross-section is analyzed on the basis of ultimate stregnth analysis.The influence of effectcoefficients on the structural system failure probability is investigated,and basic results are obtained.Ageneral program for spatial frame structures by means of the above method is developed,and verified bythe numerical examples.     

海洋油气地球化学探测方法系列与工作程序

海洋油气地球化学探测可分为两个方法系列:直接地球化学探测方法系列和间接地球化学探测方法系列。海洋油气地球化学探测分为3个阶段:区域地球化学普查、重点区带地球化学详查和局部构造地球化学评价。3个阶段的站位布设原则不同,区域地球化学普查和重点区带地球化学详查以网格取样为主,局部构造地球化学评价可以根据实际情况,采用定点、剖面和网格取样。区域地球化学探测以盆地或坳陷为目标,以评价盆地的含油气性和确定有利区带为目的;重点区带地球化学详查以重点区带为目标,以评价重点区带的含油气性和确定局部构造为目的;局部构造地球化学评价以局部构造为目标,以评价局部构造含油气性、进行局部构造排序和建议钻探井位为目的。     

三亚市近岸海域SYD1钻孔沉积物的稀土元素和物质来源

文章采集三亚市近岸海域SYD1钻孔的沉积物样品,对其稀土元素的含量进行计算和对比;通过对稀土元素δEu_(CN)、δCe_(CN)和LREE/HREE等的平均值以及球粒陨石标准化配分模式的分析和对比,探讨该区沉积物的物质来源。研究结果表明:SYD1钻孔沉积物稀土元素总量的平均值低于中国浅海沉积物和南海海域表层沉积物;稀土元素含量受沉积物粒度影响,符合"元素粒度控制律";该区沉积物源具有大陆地壳性质,以海南岛近岸陆源碎屑为主。     

Assessment of Fatigue Strength of An Offshore Floating Production and Storage Unit

The procedure of assessment of structural fatigue strength of an offshore floating production and storage and offloading unit(FPSO) in this paper. The emphasis is placed on the long-term prediction of wave induced loading, the refined finite element model for hot spot stress calculation, the combination of stress components, and fatigue damage assessment based on S-N curve.     

海洋油气开发工程环境影响评价特点浅析

相比陆上油气开发工程和其他海洋工程而言,海洋油气开发工程有其自身的特点,海洋油气开发工程环境影响评价应关注的内容与其他工程有所不同。文章通过分析海洋油气开发工程的特点以及对环境影响的特点,提出海洋油气开发工程环境影响评价要点,即包括施工期悬浮泥沙及钻井液钻屑排放对海洋生态环境的影响、运营期含油生产水排放对海洋生态环境的影响、工程建设对海洋环境敏感目标的影响、溢油事故环境风险分析、污染防治及生态保护措施,并针对目前海洋油气开发工程环境影响评价存在的问题提出改进建议。     

海南岛南部近海海底输气管道检测和安全性评价

文章采用磁力测量和侧扫声呐测量方法,对海南岛南部近海海底输气管道进行检测,并根据检测结果开展管道安全性评价。研究表明,研究区海底地形较平坦;检测范围完全覆盖预计区域;小部分管道呈现半裸露状态但未危及安全,管道整体状态良好。定期或不定期对海底输气管道进行检测,可保证管道安全,避免天然气泄漏造成海洋环境污染。     

Dynamic Characteristics and Simplified Numerical Methods of An All-Vertical-Piled Wharf in Offshore Deep Water

There has been a growing trend in the development of offshore deep-water ports in China. For such deep sea projects, all-vertical-piled wharves are suitable structures and generally located in open waters, greatly affected by wave action. Currently, no systematic studies or simplified numerical methods are available for deriving the dynamic characteristics and dynamic responses of all-vertical-piled wharves under wave cyclic loads. In this article, we compare the dynamic characteristics of an all-vertical-piled wharf with those of a traditional inshore high-piled wharf through numerical analysis; our research reveals that the vibration period of an all-vertical-piled wharf under cyclic loading is longer than that of an inshore high-piled wharf and is much closer to the period of the loading wave. Therefore, dynamic calculation and analysis should be conducted when designing and calculating the characteristics of an all-vertical-piled wharf. We establish a dynamic finite element model to examine the dynamic response of an all-vertical-piled wharf under wave cyclic loads and compare the results with those under wave equivalent static load; the comparison indicates that dynamic amplification of the structure is evident when the wave dynamic load effect is taken into account. Furthermore, a simplified dynamic numerical method for calculating the dynamic response of an all-vertical-piled wharf is established based on the P-Y curve. Compared with finite element analysis, the simplified method is more convenient to use and applicable to large structural deformation while considering the soil non-linearity. We confirmed that the simplified method has acceptable accuracy and can be used in engineering applications.     

粤东南澳岛青澳海滩侵蚀退化风险评价及其安全调控

分析了南澳岛海滩资源储量、空间分布及其开发利用现状,开展海岛海滩侵蚀风险评价,选择青澳海滩开展岸滩及其海湾海床地形、沉积物、动力泥沙调查,分析探讨了青澳海滩泥沙动力沉积特征,灾变退化过程机制,并从海滩稳定性和游客安全角度给出安全调控建议。结果表明:1)南澳岛海滩资源储量与侵蚀风险区域分异特征明显,其中青澳海滩旅游活动频繁、开发强度大,侵蚀退化风险等级高,人为破坏干扰抑制滩海泥沙交换,无序无度占滩开发与利用破坏了海滩自然演化进程,短期过量旅游活动加速海滩侵蚀退化进程;2)青澳湾沉积物以粗粒砂为主,沙源供给不足,不同岸段岸线进退与岸滩蚀淤与海滩方位、波浪动力强度强弱关系密切,具有明显的纵向沉积地貌分带特征。湾内落潮优势流(SE)优于涨潮(NW),对泥沙输运进入湾内具有抑制作用,潮周期海湾泥沙自湾内向湾外输运,泥沙以外输为主单宽输沙为3 400 t;3)青澳海滩存在严重的"无序占滩建筑,污水肆意排放,管理不规范"等问题,监测评价亦表明侵蚀退化风险巨大,游客安全面临着风险隐患,建议青澳海滩实行以生态化养护开发和"游客为中心"为理念的安全调控措施,设立红线及安全标示。该研究为岛礁生态建设、海岛保护及修复提供科学依据。