国际港口结构抗震设计标准          下载免费PDF全文

王兰民  Susumu Iai  袁中夏 《地震工程学报》2004,26(3):193-198

从设计思想、设计方法和设计步骤等方面介绍了国际航海协会制定的国际港口结构抗震设计标准。该设计标准全面引入了性态设计的思想，对不同港口结构在不同地基基础条件下的地震反应给予考虑。在应用上，该标准同时具有成熟性和灵活性，对于从事相关设计的人员是一种有益的参考。  相似文献   

甘肃文县地区阳山超大微细浸染型金矿床的成因与类型   总被引：11，自引：1，他引：11  

程斌张复新  贺国芬 《地质通报》2006,25(11):1354-1360

含矿岩石为本区泥盆系的一套Au含量较高的炭-硅-泥质地层.其中发现大量含As异常(含As约0.15%)的草莓状黄铁矿;矿体沿断裂带呈构造透镜体-扁豆体斜列等间距分布,产于断裂带中次级破碎带或顺层剪切带内;在早-中期阶段的矿化硫化物中,金以不可见金赋存于合As黄铁矿及毒砂中,含As黄铁矿发育增生环带,载金矿物主要沿片理化带呈微细浸染状分布;在中-晚期阶段的金属硫化物-石英碎裂脉体中,可见显微颗粒金;斜长花岗斑岩为地壳重熔型花岗岩,具多期次性;H、O、S同位素及流体包裹体资料表明,成矿流体以大气降水为主,岩浆水也参与成矿.由此可见,阳山金矿具沉积-岩浆叠加-构造及热液改造的多因复成特征,矿床属超大型卡林-类卡林复合型金矿床.  相似文献   

Long-term investigation of benthic fauna and the influence of treated ballast water disposal in Port Valdez,Alaska     

Blanchard AL  Feder HM  Shaw DG 《Marine pollution bulletin》2002,44(5):367-382

Benthic faunal structure and hydrocarbon concentrations in sediments were examined annually for 10 years (1989-1998) in Port Valdez, Alaska, where a near-bottom permitted discharge of treated tanker ballast waters containing residual petroleum has occurred since 1977. Measured concentrations of hydrocarbons in sediments near the discharge showed detectable increases in concentration, but on only one occasion were these increases either to levels exceeding ecotoxicological thresholds (Effects-Range Low, ER-L) or associated with alterations in the benthic community. Changes in faunal structure indicating disturbance were observed at one station near the discharge from 1995 to 1997 and were apparent as increased numbers of opportunistic taxa and anomalous trends in abundance and diversity. Minimum-effect (ME) hypotheses provided evidence of negligible to small effects on benthic infauna from disposal of treated ballast water. ME hypotheses have the potential to assist both researchers and managers by providing a tool to relate scientific results to ecological importance and decision criteria.  相似文献   

陇南阳山金矿床流体包裹体初步研究     

刘伟  范永香  余金元  徐立明 《矿产与地质》2003,17(5):616-621

陇南的阳山金矿床是产于泥盆系浅变质岩中的特大型金矿床，通过对该矿床流体包裹体的温度、盐度、密度、成矿压力及δD值等方面的研究，综合特征表明成矿流体具有浅成、中偏碱性和弱还原环境的成矿特点，综合分析认为成矿可能主要与低温热液作用有关。  相似文献   

陇南阳山金矿床流体包裹体研究     

刘伟  范永香  余金元  赵百胜 《华东地质学院学报》2003,26(4):328-336

陇南的阳山金矿床是中国人民武装警察黄金部队近年来在陕甘川交界地带发现的一个特大型金矿床。该矿床 3 0余件样品的流体包裹体分析结果表明 :1.镜下石英中流体包裹体类型丰富多样。据室温状态下流体包裹体的相态、加热状态下流体包裹体的性状及产出特征 ,鉴别出两种成因类型及九种物理状态类型 ;2 .流体包裹体显微测温结果显示本区的均一温度主要集中在 2 60～ 3 10℃ ,2 2 0～ 2 40℃ ,15 0～ 190℃等三个区间 ,流体组份体系接近于NaCl-H2 O -CO2 体系 ,,成矿流体密度估计在 0 .3 5～ 1.0 2 g·cm- 3之间 ,成矿压力估计小于 1Kbar ,流体包裹体盐度估计在 2 .5～ 6.5wb %NaCl之间 ;3 .从流体包裹体成分分析获得的 pH值在 6.91～ 7.1之间 ,还原参数H4 +CO +H2 /CO2 的摩尔数比值在 0 .0 0 9～ 0 .0 5之间 ,具有浅成中偏碱性和弱还原环境成矿特点 ;4.石英中流体包裹体的δD( -SMOW ) 值在 -92 .4‰～ -62 .9‰之间 ,δ1 8O石英 ( -SMOW ) 值在 -3 .0 9‰～ +0 .41‰之间 ,δ1 8OH2O( -SMOW ) 值在 -12 .13‰～ -8.48‰之间。综合分析认为成矿可能主要与低温热液作用有关。  相似文献   

Similarities between Yangshan Harbor area and the Yangtze estuary   总被引：1，自引：0，他引：1  

Li Yuzhong  Chen Shenliang 《地理学报(英文版)》2002,12(4):485-494

By analysis of published papers on the Yangtze estuary and hydrological and sediments data in Yangshan Harbor area, many similarities are found between Yangshan Harbor area and the Yangtze estuary. These similarities include the phenomenon of stagnating flow areas, the distributive characteristics of the highest suspended sediment concentration areas, superficial sediments and shoal bars. The stagnating flow area is the major similarity which causes other similarities. These similarities indicate that: 1) Turbidity Maximum and mouth bars in estuaries are mainly caused by the hydraulic balance of stagnating flow areas of estuaries; 2) The stagnating sand area of sands caused by stagnating flow area often locates on the narrower side of the stagnating flow area; 3) The location (or shape) of fine sediments area caused by stagnating flow area reflects the location (or shape) of the stagnating flow area. Both Yangshan Harbor area and the Yangtze estuary are the important developmental areas in the future (man-made similarity). In-depth studies on these similarities between Yangshan Harbor area and the Yangtze estuary will have momentous theoretical and practical significance.  相似文献   

Seismic characteristics of a reef carbonate reservoir and implications for hydrocarbon exploration in deepwater of the Qiongdongnan Basin,northern South China Sea   总被引：2，自引：0，他引：2  

Shiguo Wu  Shengqiang Yuan  Gongcheng Zhang  Yubo Ma  Lijun Mi  Ning Xu 《Marine and Petroleum Geology》2009

Our analysis of approximately 40,000 km of multichannel 2-D seismic data, reef oil-field seismic data, and data from several boreholes led to the identification of two areas of reef carbonate reservoirs in deepwater areas (water depth ≥ 500 m) of the Qiongdongnan Basin (QDNB), northern South China Sea. High-resolution sequence stratigraphic analysis revealed that the transgressive and highstand system tracts of the mid-Miocene Meishan Formation in the Beijiao and Ledong–Lingshui Depressions developed reef carbonates. The seismic features of the reef carbonates in these two areas include chaotic bedding, intermittent internal reflections, chaotic or blank reflections, mounded reflections, and apparent amplitude anomalies, similar to the seismic characteristics of the LH11-1 reef reservoir in the Dongsha Uplift and Island Reef of the Salawati Basin, Indonesia, which house large oil fields. The impedance values of reefs in the Beijiao and Ledong–Lingshui Depressions are 8000–9000 g/cc × m/s. Impedance sections reveal that the impedance of the LH11-1 reef reservoir in the northern South China Sea is 8000–10000 g/cc × m/s, whereas that of pure limestone in BD23-1-1 is >10000 g/cc × m/s. The mid-Miocene paleogeography of the Beijiao Depression was dominated by offshore and neritic environments, with only part of the southern Beijiao uplift emergent at that time. The input of terrigenous sediments was relatively minor in this area, meaning that terrigenous source areas were insignificant in terms of the Beijiao Depression; reef carbonates were probably widely distributed throughout the depression, as with the Ledong–Lingshui Depression. The combined geological and geophysical data indicate that shelf margin atolls were well developed in the Beijiao Depression, as in the Ledong–Lingshui Depression where small-scale patch or pinnacle reefs developed. These reef carbonates are promising reservoirs, representing important targets for deepwater hydrocarbon exploration.  相似文献   

潮流作用下洋山港水域悬沙和底沙的交换   总被引：2，自引：0，他引：2  

陈沈良  李向阳  俞航  谷国传 《海洋学研究》2008,26(1):11-17

通过对泥沙起动流速、淤积流速和不淤流速的计算,划定了悬沙和底沙交换的各个时段,提出了冲刷悬沙浓度、淤积悬沙浓度和不淤悬沙浓度的概念及其计算方法;继而导出了潮流作用下悬沙和底沙在交换层面上单位面积的日交换量计算式,并用于洋山港水域的冲淤计算。结果表明:自然状况下洋山港水域北部年淤积量为37.5 kg/m2,淤高了1.77 cm/a,属微淤;中部年冲刷量为10.0 kg/m2左右,刷深不超过0.52 cm/a,可认为冲淤平衡;南部年冲刷量为55.5 kg/m2,刷深了2.60 cm/a,属微冲。这一结果与该水域海床的自然冲淤状况相吻合。  相似文献   

甘肃省文县阳山金矿床地质及同位素特征   总被引：6，自引：0，他引：6  

杨贵才  齐金忠  董华芳  郭俊华  李志宏 《地质与勘探》2007,43(3):37-41

阳山金矿床位于陕甘川交界地带,在大地构造位置上属西秦岭南亚带.矿床产于中泥盆统三河口组浅变质岩地层中,受文县弧形构造控制.矿体在平面上呈舒缓波状,在剖面上为脉状、似层状,矿石中金属矿物主要有黄铁矿、毒砂和辉锑矿,金主要以微细粒金赋存于黄铁矿、毒砂和黏土矿物中.矿床的钾-氩、氩-氩、氢、氧、硫、碳同位素研究表明,阳山金矿形成于侏罗纪早期(195Ma),与区域上三叠纪末期-侏罗纪早期的岩浆-构造活动关系密切,其不同于典型的卡林型金矿以及类卡林型金矿,其成矿流体及成矿物质均与岩浆热液活动有关.  相似文献   

Morphological characteristics and medium-term evolution of the beaches between Ceuta and Cabo Negro (Morocco)   总被引：1，自引：0，他引：1  

G. Anfuso  J. A. Martínez del Pozo  D. Nachite  J. Benavente  A. Macias 《Environmental Geology》2007,52(5):933-946

This work presents the results of a combined study on the beach morphology and the evolution at short- and medium-term of the littoral between Ceuta and Cabo Negro (Morocco). It is an interesting sector showing a great increase of human occupation and coastal structures. The monitoring program allowed for the reconstruction of the beach morphological behavior and the seasonal changes. The studied beaches presented reflective profiles recording little seasonality, with the most notable morphological changes being strictly related to storms. Surf Similarity and Surf Scaling parameters highlighted the existence of intermediate and reflective beach states, characterized by plunging breakers. Aerial photographs and a satellite image have been geo-referenced and elaborated with GIS tools to reconstruct the short- and medium-term evolution of the littoral and the sediment transport pathways. The littoral showed important erosion at short- and medium-term related to a negative sedimentary budget because of offshore transport. Sand accumulation was recorded close to the main ports, i.e., Marina Smir and Marina Kabila. These port structures constituted impermeable, fixed limits, which divided the studied area into littoral cells. Other free, transit limits were also observed.  相似文献