山东省蓬莱西海岸侵蚀及其与地貌环境的关系

蓬莱市西庄至栾家口海岸,1985年以来蚀退明显加剧。从地貌环境分析认为,由于人为挖砂改变了海底和海滩的地貌环境。从而导致了近岸的水动力增强,加之海岸抗蚀性差以及入海陆源物质贫乏和海滩物质亏损,是本区海岸近期蚀退的重要原因。     

对鲁东南沿海地貌发育问题的初步探讨

山东东南海岸大致界于胶州湾与日照岚山头之间(图1)。对这一区间海岸地貌的研究,直到本世纪五十年代中期,尚无专题论文发表。仅在本世纪初,德国地质学家李希霍芬、日人福地信世等对青岛及胶州湾地区的地质、地理作过论述;三十年代,我国地质学家叶良辅、喻德渊、王绍文的论文亦侧重于青岛附近的地质研究,而对本区海岸地貌的问题介绍不多。五十年代末,孙庆基等对胶州湾及青岛海岸地貌发表了专文。此     

山东省东部海岸湾岛资源旅游潜力分析

本研究范围北起山东半岛的成山角 (37°24′N ,122°42′E) ,南至苏鲁交界处的绣针河口(37°24′N ,122°42′E)。研究区东临南黄海 ,是我国北方主要的基岩港湾海岸分布区 ,海岸岩石特征为燕山期花岗岩为主 ,间有胶东元古代古老变质岩分布。海岸线全长300km多。海岸地貌特征是湾岛众多、海域开阔、生态环境优美。面积大于1km2的海湾有37个 ,大于500m2的海岛142个。海岸跨越威海、青岛和日照3个旅游区。区内具有丰富的海岛与海湾地学旅游资源 ,优美的风光、迷人的阳光沙滩、宜人的气候是本区主要的旅游资源特点。独特的生态环境和优越的区位条件决定了本区是一个具有巨大潜力的滨海旅游业发展区域。本文将其分为威海东南部、青岛近海和日照近海3个区 ,对各区地貌特征及旅游资源进行了研究 ,并针对各区旅游资源开发现状和特色 ,对其旅游开发潜力作了布局分析 ,提出了相应的旅游设计建议     

山东威海滨海沙滩动力地貌特征

通过现场调查数据和动力地貌分析,探讨了山东威海滨海沙滩剖面形态及其动力学特征。将研究区砂质海岸地貌类型分为岬湾型、沙坝泻湖型2种,其中沙坝泻湖型又可分为沙坝型,沙咀型和连岛型3种亚型。在海岸地貌类型、海洋动力和人为因素影响下,研究区的沙滩形态表现出显著的差异。依据破波尺度参数ε的大小,研究区沙滩可分为反射型、沙坝-槽谷型、低潮阶地型和耗散型4种类型。沙滩开发利用和养护对策的制定,应该针对海岸地貌类型和沙滩形态而区别对待。     

中国的海岸带调查和管理现状

中国大陆有18000km的海岸线,有基岩海岸、砂砾质海岸、淤泥质海岸、红树林海岸和珊瑚礁等多种类型.海岸带面积广阔,具有丰富的石油、滨海砂矿和生物资源,据初步估计,滩涂面积约2万km~2.我国沿海地区人口稠密、城市集中、经济发达、科技力量雄厚.开发利用海岸带资源是发展我国海洋事业的重要组成部分.为了全面齐发利用我国海岸带资源,早于1960年至1966年,国家即有计划地组织过全国海岸带的调查和研究.第二次开展的全国海岸带和海涂资源综合调查,始于1980年,至1986年完成.调查范围为:北起鸭绿江口,南至北仑河河口,包括辽宁、河北、天津、山东、江苏、上海、浙江、福建、广东和广西十个沿海省市的海岸带.调查区以海岸线为准,一般向内陆延伸10km,向海延伸至10—15m的等深线.调查内容为地质、地貌、底质、土壤、生物、水文、气象、化学等方面.     

山东半岛海岸地貌与波浪、潮汐特征的关系

本文通过山东半岛海岸地貌类型与沿岸波浪、潮汐发生学关系的对比分析,引入浪潮作用指数 K,K=2.5×(H/R),H 为平均波高,R 为平均潮差.K>1时,海岸地貌演变的动力以波浪作用为主,海岸极少发育潮汐叉道和落潮三角洲,但连岛坝发育较好;K<1时,海岸地貌演变的水动力以潮汐作用为主,落潮三角洲、潮汐叉道较发育;K 值接近于1时,发育潟湖等过渡海岸地貌类型.     

论芝罘连岛沙坝的形成

芝罘连岛沙坝是世界海岸的一个典型,为国内外地质、地理学界颇富盛名之地。早在解放前,就有人对芝罘连岛作过初步观察,并论述了其成因,本文试图通过对它的研究,来探讨山东半岛海岸升降问题、发展连岛沙坝形成的理论。中国科学院海洋研究所于1958年首次进行渤海综合调查时,曾初步观察了芝罘连岛及其附近的海岸,并编绘出了海岸地貌图和调查报告。1960年,为开展我国海岸调查研究,我们选择山东半岛北岸的芝罘连岛及其附近的海岸带为一典型海岸段进行了地质、地貌调查研究和近岸区波浪、流的观测工作。后来,水产和港口等地方各建设部门又提出了查明海岸冲汙规律、泥沙动态、护岸工程与采砂     

山东半岛北部全新世后期砂坝-溩湖发育与岸线演变形式

山东半岛北部海岸为岬湾式海岸,这里砂坝-潟湖广泛分布,形成本区海岸最重要的地貌景观。本区从湖间带至沿岸平原,从表层至地下,组成了一个形成于不同时代的砂坝-潟湖群。本区全新世后期的砂坝-潟湖的发育与演变,导致岸线向海推进。因此岸线的演变与砂坝-潟湖的发育有着密切的联系。从本区砂坝-潟湖的研究可知,自大西洋期以后,特别是距今4345a(~(14)C测年)以来,随着砂坝-潟湖的不断形成和衰亡及并陆,使陆域扩大,岸线不断向海移动。     

地貌素描在黄渤海海岸地貌研究中的应用

地貌素描是地貌调查的一种重要方法，它能直观而又突出地表现典型地貌类型的特征形态和三维空间透视感。与摄影方法相比．地貌素描不受光线和摄影角度的限制，是外业摄影方法的一种补充手段。本文选取了作者多年来创作的部分典型海岸地貌素描图，较逼真地说明了海岸地质构造和地貌特点，阐述了地貌素描在海岸地貌调查中的作用。     

《海岸工程》征稿简则

一、《海岸工程》由青岛市海岸工程学会和国家海洋局第一海洋研究所联合主办。它是海岸环境和工程科学的综合性学术刊物。二、征稿内容1、海岸工程环境(浪、潮、流等);动力地貌,工程地质,泥沙洄淤;海岸工程规划、设计、施工等方面的论文,调查研究和分析实验报告。2、国内外海岸工程科学的综合评述,重要书刊和论文评介。     

Microbial Biomass and Organic Nutrients in the Deep-Sea Sediments of the Central Indian Ocean Basin

In order to assess the impact of deep-sea mining on the in situ benthic life, we measured the microbial standing stock and concentration of organic nutrients in the deep-sea sediments of the Central Indian Ocean Basin in the Indian pioneer area. Sediments were collected using box core and grab samples during September 1996. The total bacterial numbers ranged from 10 10 -10 11 cells per g -1 dry weight sediment. There was a marginal decrease in the number of bacteria from surface to 30 cm depth, though the subsurface section registered a higher number than did the surface. The highest numbers were encountered at depths of 4-8 cm. The retrievable number of bacteria were two orders less in comparison with the direct total counts of bacteria. An almost homogeneous distribution of bacteria, total organic carbon, living biomass, and lipids throughout the depth of cores indicates active microbial and benthic processes in the deep sea sediments. On the other hand, a uniform distribution of total counts of bacteria, carbohydrates, and total organic carbon in all the cores indicates their stable nature and suggests that they can serve as useful parameters for long-term monitoring of the area after the benthic disturbance. Further studies on temporal variability in this region would not only verify the observed norms of distribution of these variables but would also help to understand restabilization processes after the simulated benthic disturbance.     

Geoacoustic Inversion via Genetic Algorithm and Its Application to Manganese Sediment Identification

An acoustic inversion method using a wide-band signal and two near field receivers is proposed and applied to multiple layered seabed models including a manganese sediment. The inversion problem can be formulated into a probabilistic model comprised of signals, a forward model, and additive noise. The forward model simulates wide-band signals, such as chirp signals, and is chosen to be the source-waveletconvolution plane wave modeling method. The wavelet matching technique, using weighted least-squares fitting, estimates the sediment sound-speed and thickness on which determination of the possible numerical ranges for a priori uniform distribution is based. The genetic algorithm is applied to a global optimization problem to find a maximum a posteriori solution for determined a priori search space. Here the object function is defined by an L 2 norm of the difference between measured and modeled signals. Not only the marginal pdf but also its statistics are calculated by numerical evaluation of integrals using the samples selected during importance sampling process of the genetic algorithm.     

Sea Levels and Coastal Inundation Due to Tropical Cyclones in Indian Coastal Regions of Andhra and Orissa

Coastal inundation associated with extreme sea levels is the main factor which leads to the loss of life and property whenever a severe tropical cyclonic storm hits the Indian coasts. The Andhra and Orissa coasts are most vulnerable for coastal inundation due to extreme rise in sea levels associated with tropical cyclones. Loss of life may be minimized if extreme sea levels and associated coastal flooding is predicted well in advance. Keeping this in view, location specific coastal inundation models are developed and applied for the Andhra and Orissa coasts of India. Several numerical experiments are carried out using the data of past severe cyclones that struck these regions. The simulated inland inundation distances are found to be in general agreement with the reported flooding.     

Deep-Sea Sediment Compression Curves: Some Controlling Factors, Spurious Overconsolidation, Predictions, and Geophysical Reproduction

Oedometer tests have been carried out on 70 undisturbed surficial clays (at approximately 250 mm below the mudline), mostly collected by free-fall corers from sites widely scattered throughout the deep-sea North Atlantic. Acoustic measurements were also made, initially on contiguous samples and ultimately on the same sample using a geophysically instrumented oedometer which also collected electrical resistivity data. Apart from those quiescent areas below the carbonate compensation depth, such as north of the West Indies where very fine clays exist, most of the samples are silty clays whose geotechnical-geophysical properties are dependent on the type of clay minerals present (and their ability to take in moisture), the sand-size fraction, and the quantity of carbonate present. Thus the pure clays have high compressibilities which decrease on the addition of coarse particles, while the converse is true for the acoustic parameters, these increasing with the sand fraction. Using the notion of the intrinsic compression line for all samples, and comparison to it of the measured compression curves, it is clear that, contrary to some previously held ideas, most deep-sea clays are normally consolidated; the addition of carbonate has the effect of creating an open, stronger sediment skeleton. Interestingly, where information is available, the variation with depth of a sample's acoustic velocity follows the void ratio pressure relationship of the compression curve. This allows the construction of an in-situ sediment compression curve using the in-situ geophysical observations.     

INFORMATION FOR AUTHORS

<正>Acta Oceanologica Sinica(AOS)is a comprehensive academic journal edited by the Editorial Committee of Acta Oceanologica Sinica and is designed to provide a forum for important research papers of the marine scientific community which reflect the information on a worldwide basis.The journal publishes scholarly papers on marine science and technology,including physics,chemistry,biology,     

Evaluation of the Risk of Marine Slope Instability: A Pseudo-3D Approach for Application to Large Areas

This article presents a methodology developed to evaluate the instability of submarine slopes that extend over a large area. Special attention was paid to (1) the complex geometry (bathymetry) and the expanse of the slope, (2) the heterogeneity of the sediment, and (3) the distribution of the pore pressure. The safety factor was considered as a spatially varying quantity. The General Formulation (GLE, Fredlund and Krahn 1977), which fully satisfies equilibrium conditions, was used for evaluating the stability of the marine slope. The submarine slope failure, which occurred on 16 October 1979 during the construction of the new Nice airport, was studied in order to test the developed model. Geotechnical parameters were taken from experimental tests carried out by IFREMER on 19 cores extracted at different depths (from 27 m to 1300 m) (Cochonat, Bourillet, and Savoye, 1993; Mulder et al., 1994). Many scenarios were proposed in order to explain the cause of the Nice slope failure (Habib, 1994). In this article, two of those scenarios were tested. Simulation results are presented and discussed.     

Sea Levels and Western Boundary Flow Near a Tectonic Zone in the Northern Pacific

This article concerns an interrelation between the sea levels and the western boundary flow near a tectonic boundary in a local zone in the Northwestern Pacific. In this zone, sea level variations at stations located on the coast facing the Pacific are studied to find the interrelation between variations of the Kurosio flow as an index of the distance of the flow axis off a specific coast. The result is discussed after data processing of the monthly means of the sea levels, and a notice is taken of variations caused by active crustal upheavals during a seismic event, a local earthquake.     

Role of Siliceous Fossil Dissolution in Downcore Variations of Grain Size and Water Content: Western Margin of Clarion-Clipperton Fracture Zone, NE Equatorial Pacific

Grain size and water content in box-core sediments from the Clarion-Clipperton fracture zone (C-C zone) in the northeast equatorial Pacific were analyzed in detail to understand the downcore variations across a hiatus between Quaternary and Tertiary layers. Grain-size distributions in the topmost core sediments show two modes: a coarse mode (peaked at 50 μm) and a fine mode (at 2-25 μm). The coarse mode disappears gradually with depth accompanied by the dissolution of siliceous fossil tests, whereas the fine mode coarsens due to the formation of authigenic minerals. Water content increases abruptly across a color boundary between an upper pale brown layer and a lower dark brown layer that is the hiatus between Quaternary and Tertiary layers. Abundant smectites and microvoid molds, which are created by the prolonged fossil dissolution in the underlying sediment, are attributed for the abrupt downcore variation of water content. Overall variations in grain size and water content in the topmost core sediments in the western C-C zone are possibly constrained by the dissolution of biogenic siliceous fossils. Variations in geotechnical properties related to these changes must be considered in the design of nodule collectors.     

A Nondestructive Technique for Predicting the In Situ Void Ratio for Marine Sediments

This study tests the hypothesis that the in situ void ratio of surficial marine sediments may be predicted from shear wave velocity-depth data with a reliability equal to that of other methods currently available. Shear wave velocity is fundamentally controlled by the number of grain-to-grain contacts per unit volume of material and by the effective stress across those contacts. In this study, three previously established empirical formulae are used to predict void ratio from velocity-depth data. Field data were acquired along a transect off the northern Californian coast across which water depth increased from 35 to 70 m and seafloor sediment type varied from sand to silty-sand, respectively. A towed seafloor sled device was used to collect shear wave refraction data, and a marked, systematic decrease in velocity was observed along the line, ranging from 35-70 m/s for the coarse, near-shore material to 25-40 m/s for the finer, offshore deposits. Void ratios predicted from these velocities were compared with data measured directly from box-core samples. Of the formulae used for prediction, two agree remarkably well with the control data. Both predicted and control values increase from 0.6-0.8 for the sandy material to 1.1-1.5 for the silty-sand. Thus, this study does not disprove the hypothesis set and demonstrates the potential of field shear wave velocity-depth data as a means of delineating spatial variation in void ratio for surficial marine sediments in a remote, nondestructive manner.