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1.
This article presents general information on environmental geotechnical problems along the Taiwan Strait Tunnel (TST) route including sea-floor characteristics. The term apparent sea-floor is introduced. This layer is due to land erosion washing down and settling in the Taiwan Strait. The depth of ocean water along the Taiwan Strait is estimated. Various soil, and rock types and marine sediments along the coastline of mainland, Taiwan Strait, and Taiwan Islands are presented. Foundation problems under adverse marine environments are discussed.  相似文献   

2.
This article presents general information on environmental geotechnical problems along the Taiwan Strait Tunnel (TST) route including sea-floor characteristics. The term apparent sea-floor is introduced. This layer is due to land erosion washing down and settling in the Taiwan Strait. The depth of ocean water along the Taiwan Strait is estimated. Various soil, and rock types and marine sediments along the coastline of mainland, Taiwan Strait, and Taiwan Islands are presented. Foundation problems under adverse marine environments are discussed.  相似文献   

3.
For Future cross-sea passage spanning the Taiwan Strait, no matter what kind of scheme is adopted, its design, construction, and administration are closely related to marine hydrological and meteorological environmental elements. In this article, based on a great number of observed data, analyses for wave, typhoon, and monsoon conditions in the Taiwan strait region are made and their distributional features and character values are given. Especially, the wave height and occurrence frequencies of disastrous waves are analyzed, and the values of design wave parameters (wave height and period with a given return period) are estimated to use for the reference of the scheme optimization and project preliminary program of cross-sea passage spanning the strait.  相似文献   

4.
For Future cross-sea passage spanning the Taiwan Strait, no matter what kind of scheme is adopted, its design, construction, and administration are closely related to marine hydrological and meteorological environmental elements. In this article, based on a great number of observed data, analyses for wave, typhoon, and monsoon conditions in the Taiwan strait region are made and their distributional features and character values are given. Especially, the wave height and occurrence frequencies of disastrous waves are analyzed, and the values of design wave parameters (wave height and period with a given return period) are estimated to use for the reference of the scheme optimization and project preliminary program of cross-sea passage spanning the strait.  相似文献   

5.
Marine fine-grained soils are well known for their compressibility, which is typically measured and reported in terms of compression index, Cc. The difficulties associated with measuring Cc have resulted in growing research interest in statistics-based estimates (i.e., correlation equations). Although many empirical and semiempirical correlations exist for estimating Cc, most available correlations are based on either data from nonmarine soils or data collected from Japanese and Korean marine clays. Thus, there are few correlations for marine clays from other parts of the world. In the present study, two independent databases which contain a total of 1,000 data points from 170 different sites worldwide are used to build and validate statistically significant correlations for estimating compression index of marine soils. The results of this study suggest that (1) the proposed correlation equations provide quite good estimates of Cc for marine soils with different stress histories and sensitivities and (2) most of the existing models have unacceptable performance when they are applied to marine soils.  相似文献   

6.
I~IOW~ne nelnatode is a ban gIOup of benthic OrgAnsrns. Abbot 5 000 spotes Of free-livingnelnatedes have ben dedbo so far, and it has ho estimated that abbot 20 (XX) are as yetunknoWn. Chinese bothologist has Paid attention to marine nelnatodes in China seas in yare. The spatial distribution and shoes commotion of marine nelnatedes in the HUanghe EstUary, Qinhuangdao waters, QingdaO Bay and Xiamen ~ have ho reported (Zhang etal., 1990, 1991, 1993; ac and Li, 1998). ~ new shoes in the…  相似文献   

7.
台湾海峡地理位置独特,西侧海域海湾 岛屿系统普遍发育,显著影响了海域流场分布。同时,海峡西岸经济区的快速发展对区域海洋动力环境背景场及其变化的精细认识提出了更高的要求。福建莆田南日岛西侧南日水道是连通兴化湾与平海湾的主要水道,是区域海洋动力环境的“咽喉”所在,在区域海洋环境保护与科学开发利用中居于至关重要的位置。为了全面认识台湾海峡西侧海湾 岛屿系统影响下区域海洋动力环境背景场的年季变化,本研究利用布放在南日水道的座底观测系统获得的周年海流资料,结合同期气象风场资料,通过数据统计分析、调和分析、滤波处理和小波变化等手段,研究了南日水道内海流的季节变化规律和驱动余流的动力要素,初步探讨了热带气旋等对海洋动力演化过程的影响。研究结果表明,研究海域潮流为不正规半日浅海潮流,并具有明显的半月周期,涨潮流大于落潮流,涨潮流主方向为 WNW 向,落潮流主方向为 SE—ESE向。旋转谱结果表明,研究海域以半日潮为主,逆时针能量强于顺时针,惯性周期无明显的谱峰。潮流强度的季节变化特征为冬季最强,秋季、春季次之,夏季最弱。夏、秋季的余流流速较其他季节明显偏大,表层余流有明显的季节特征,底层余流全年为北向流。观测点余流主要由风引起,二者有很好的相关性,但频率统计结果显示二者方向不一致,表明余流在地形的作用下发生了转向,其中潮致余流对表层余流贡献较小。小波能量图表明,双台风(热带气旋)期间风和余流均存在1 d及6 d左右的周期信号,二者密切相关。本研究成果对于区域海洋环保以及海域科学开发与应用具有重要的现实意义。  相似文献   

8.
关于台湾海峡分界的探讨   总被引:1,自引:0,他引:1  
周定成 《台湾海峡》2010,29(2):149-153
台湾海峡介于台湾岛与大陆之间,是东海与南海的通道.关于台湾海峡范围的划分,海峡之东常以台湾岛两端(北为富贵角,南为鹅銮鼻)为界;海峡之西以大陆的平潭岛等为北界,东山岛或南澳岛为南界.为了更客观和准确地划分台湾海峡范围,本文根据海洋地理学中"海峡"的概念及对世界海峡类似实例的分析,并按照台湾海峡区域地形、地质等特征进行了分界.作者认同台湾海峡北口位于福建省平潭岛至台湾富贵角,但认为其南口应位于广东南澳岛至台湾曾文溪河口南岸.在此南、北口之间为台湾海峡范围.台湾海峡地形、地质等特征明显,与台湾及大陆紧密关联,并具有东海延伸入内的特点.而北口之北的闽东北海底,海峡特征明显消失.此南口为东海与南海的交汇处,其南属于南海的台湾浅滩及其外缘,其地形、地质特征也与海峡的显著不同.本研究结果对于更准确地划分台湾海峡范围及区域海洋研究与实践等方面都具有多方面的意义.  相似文献   

9.
For decades, various well-known empirical correlations have been established and commonly used to estimate the undrained shear strength of normally consolidated clays in geotechnical practice. However, there are still many contradictory cases regarding the validity of these correlations, so their applicability and reliability are questionable. In this study, an extensive geotechnical database for normally consolidated clays has been compiled. Next, a Bayesian nonparametric method is exploited to identify the most critical soil index properties in inferring the undrained shear strength and a new predictive model is proposed. Finally, the performance of the proposed predictive model is assessed and compared with two well-known correlations using an independent testing database. It confirms that the proposed model not only possesses high predictability, but also provides superior performance over other existing empirical correlations.  相似文献   

10.
台湾海峡地质构造特征   总被引:11,自引:1,他引:11  
杨肖琪  宋文隆 《台湾海峡》1996,15(2):127-136
台湾海峡及其邻区构造可分为3个一级构造单元,即闵浙中生代隆起区、台湾峡新生代坳陷区和台湾新生代岛弧褶断区。其中台湾海峡新生代坳陷区由海峡的主体和台湾西部兵陵平原区组成,它的东、西边界分别是台湾屈尺-老浓断裂带和粤滨外深断裂带。本文在以往海峡西岸东南海海长东-南澳断裂带研究基础上,对近年来台湾海峡、特别是海峡新生代坳陷区各次一级构造单元的深部地质结构,海底地形地貌、沉积特征、断裂构造、火成岩分布和地  相似文献   

11.
台湾海峡中北部海洋线虫群落的种类组成及分布   总被引:3,自引:0,他引:3  
1998年2月对台湾海峡中北部3个断面13个取样站进行了自由生活海洋线虫调查,获得了海洋线虫100种,隶属于3目28科91属,其中密度较高的种有萨巴线虫(Sabatieria sp.1)、变异矛咽线虫(Dorylaimopsis variabilis)、Vasostoma sp.、花斑线虫(Spilophorella sp.)、吞咽线虫(Daptonema sp.)、Linhystera sp.1、吸咽线虫(Halalaimus sp.1)和(Filoncholaimus sp.)等。虽然这些海洋线虫绝大多数只鉴定江口外海降低。从优势种分布看,不同取样站其密度差异很大。海洋线虫的取食类型以选择性食沉积物者(1A)占优,有38种,但刮食性种类(2A)和非选择性食沉积物者(1B)也分别为29种和25种,表明了台湾海峡中北部海洋吸虫取食类型的复杂性。文中还探讨了海洋线虫分布与海流等环境因子的关系。  相似文献   

12.
晚玉木冰期台湾海峡的沉积环境   总被引:4,自引:1,他引:3  
对台湾海峡西部海域及河口平原14个钻孔剖面经孢粉、14C年龄和古地磁测定确定为晚玉木冰期的沉积层(Q33)样品进行了硅藻、有孔虫分析.结果表明,该时期海域的沉积层均属海相沉积,而河口平原区的沉积层则由海相和陆相地层交互组成.据此,提出了台湾海峡在晚玉木冰期属于水深在30~50m的浅海沉积环境的观点;阐述了这一与全球性气候冷暖更替所引起的海平面升降不一致现象是由于晚玉木冰期台湾海峡的地壳运动正处于间歇性下降时期,从而保持了浅海环境.  相似文献   

13.
GPS observation indicates that the Fujian coastal region of China mainland, the region of Taiwan Strait and northern Taiwan island all show a generally homogenous horizontal motion with weak deformation. Historical earthquake record over more than 800 years and modern instrumental data reveal that there is potential seismic risk in and around Taiwan Strait region. After the National Seismic Zoning Map of China (2001) the expected seismic risk in northern part of the Taiwan Strait is lower than that in middle and southern part. The suggested northern route of the Taiwan Strait passage project seems to be relatively save seismically.  相似文献   

14.
GPS observation indicates that the Fujian coastal region of China mainland, the region of Taiwan Strait and northern Taiwan island all show a generally homogenous horizontal motion with weak deformation. Historical earthquake record over more than 800 years and modern instrumental data reveal that there is potential seismic risk in and around Taiwan Strait region. After the National Seismic Zoning Map of China (2001) the expected seismic risk in northern part of the Taiwan Strait is lower than that in middle and southern part. The suggested northern route of the Taiwan Strait passage project seems to be relatively save seismically.  相似文献   

15.
詹国能 《台湾海峡》1996,15(4):352-356
本文应用任意3a中850hPa上的风及500hPa和地面气象资料,对台湾海峡地区出现低空急流的天气气候特征,形成急流的天气背景及其影响下的天气进行初步分析。结果表明,台湾海峡地区850hPa低空急流具有明显的季风特征和特定的地理影响。  相似文献   

16.
The necessity and the preliminary tentative plan for the construction of the undersea tunnel across Taiwan Strait are expounded in this atricle. The strait undersea tunnels, which have been built and investigated in the world, and their engineering characteristics and construction methods have been introduced herein briefly.?Taiwan has been a part of China since ancient times and the people between the mainland and Taiwan are kindred compatriots in the extended family of the Chinese multinational country. For a long time, the people between southeast of China and Taiwan have had frequent communication in economy and culture. With the progress of times and the need of development, it has been put forward to build a safe and reliable undersea tunnel that is not affected by the environment across Taiwan Strait, and one which is also a magnificent project for the China in the long-term.?Whether by using a bridge or an undersea tunnel or both across the strait is a problem worthy of further research. According to such conditions as the weather of Taiwan Strait, depth of water, undersea terrain, possibility of engineering and hydrological geology under the sea, as well as the possibility of Taiwan Strait as a main shipping passage from south to north of China and the experience of existing passage across strait in the world, the primary analysis shows that the scheme of an undersea tunnel should be considered. Therefore the concept of the undersea tunnel engineering across Taiwan Strait is introduced in detail here.  相似文献   

17.
海底沙体是海洋资源开发利用、环境保护、灾害防治和军事行动等必须密切关注的底质类型。台湾海峡沙体面积分布广泛,主要有台湾浅滩、台中浅滩及海峡内受中小型山溪性河流影响的沙体。近年来,台湾浅滩沙体空间分布、大型沙波与小型沙波形态特征及剖面结构研究等领域取得了许多新进展;台中浅滩不同区域的沙体演化对应了地貌发育的不同阶段;而海峡西侧陆架上残留的中小河流沙体地貌也获得了一些新发现。本文归纳了台湾海峡窄陆架上不同沙体的平面分布特征、剖面结构及成因。今后工作的重点应聚焦于进一步获取不同区域高分辨率的地层、地貌证据,并进行对比研究。这些工作能深化对末次盛冰期以来台湾海峡不同地区沙体成因、关联及演化的认识,并有助于了解人类海洋活动与海底沙体演化的响应关系,丰富海底沙体发育和演化理论。  相似文献   

18.
The necessity and the preliminary tentative plan for the construction of the undersea tunnel across Taiwan Strait are expounded in this atricle. The strait undersea tunnels, which have been built and investigated in the world, and their engineering characteristics and construction methods have been introduced herein briefly. Taiwan has been a part of China since ancient times and the people between the mainland and Taiwan are kindred compatriots in the extended family of the Chinese multinational country. For a long time, the people between southeast of China and Taiwan have had frequent communication in economy and culture. With the progress of times and the need of development, it has been put forward to build a safe and reliable undersea tunnel that is not affected by the environment across Taiwan Strait, and one which is also a magnificent project for the China in the long-term. Whether by using a bridge or an undersea tunnel or both across the strait is a problem worthy of further research. According to such conditions as the weather of Taiwan Strait, depth of water, undersea terrain, possibility of engineering and hydrological geology under the sea, as well as the possibility of Taiwan Strait as a main shipping passage from south to north of China and the experience of existing passage across strait in the world, the primary analysis shows that the scheme of an undersea tunnel should be considered. Therefore the concept of the undersea tunnel engineering across Taiwan Strait is introduced in detail here.  相似文献   

19.
The interdependence between the seismo-acoustic properties of a marine sediment and its geotechnical/physical parameters has been known for many years, and it has been postulated that this should allow the extraction of geotechnical information from seismic data. Though in the literature many correlations have been published for the surficial layer, there is a lack of information for greater sediment depths. In this article, a desktop study on a synthetic seafloor model illustrates how the application of published near-surface prediction equations to subsurface sediments (up to several tens of meters burial depth) can lead to spurious predictions. To test this further, acoustic and geotechnical properties were measured on a number of sediment core samples, some of which were subjected to loading in acoustically-equipped consolidation cells (oedometers) to simulate greater burial depth conditions. For low effective pressures (representing small burial depths extending to around 10 meters subsurface), the general applicability of established relationships was confirmed: the prediction of porosity, bulk density, and mean grain size from acoustic velocity and impedance appears generally possible for the investigated sedimentary environments. As effective pressure increases through, the observed relationships deviate more and more from the established ones for the near-surface area. For the samples tested in this study, in some instances increasing pressure even resulted in decreasing velocities. There are several possible explanations for this abnormal behavior, including the presence of gas, overconsolidation, or bimodal grain size distribution. The results indicate that an appropriate depth correction must be introduced into the published prediction equations in order to obtain reliable estimates of physical sediment properties for greater subsurface depths.  相似文献   

20.
The interdependence between the seismo-acoustic properties of a marine sediment and its geotechnical/physical parameters has been known for many years, and it has been postulated that this should allow the extraction of geotechnical information from seismic data. Though in the literature many correlations have been published for the surficial layer, there is a lack of information for greater sediment depths. In this article, a desktop study on a synthetic seafloor model illustrates how the application of published near-surface prediction equations to subsurface sediments (up to several tens of meters burial depth) can lead to spurious predictions. To test this further, acoustic and geotechnical properties were measured on a number of sediment core samples, some of which were subjected to loading in acoustically-equipped consolidation cells (oedometers) to simulate greater burial depth conditions. For low effective pressures (representing small burial depths extending to around 10 meters subsurface), the general applicability of established relationships was confirmed: the prediction of porosity, bulk density, and mean grain size from acoustic velocity and impedance appears generally possible for the investigated sedimentary environments. As effective pressure increases through, the observed relationships deviate more and more from the established ones for the near-surface area. For the samples tested in this study, in some instances increasing pressure even resulted in decreasing velocities. There are several possible explanations for this abnormal behavior, including the presence of gas, overconsolidation, or bimodal grain size distribution. The results indicate that an appropriate depth correction must be introduced into the published prediction equations in order to obtain reliable estimates of physical sediment properties for greater subsurface depths.  相似文献   

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