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101.
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   
102.
利用矿物地质温压计估算变质高峰期温压条件、退变质作用温压条件。研究表明,本区为鲁苏构造带的北延部分,代表本区晚元古代华南陆块与华北陆块的碰撞及三叠纪华北陆块向华南陆块推覆事件的发生和演化。  相似文献   
103.
New PCR primers (N=18) were designed for the isolation of complete SSU to LSU rDNA sequences from the dinoflagellateAlexandrium tamarense. Standard PCR, employing each primer set selected for amplifications of less than 1.5 kb, successfully amplified the expected rDNA regions of A. tamarense (Korean isolate, HY970328M). Complete SSU, LSU rDNAs and ITS sequences, including 5.8S rDNA, were recorded at 1,800 bp, 520 bp and 3,393 bp, respectively. The LSU rDNA sequence was the first report inAlexandrium genus. No intron was found in the LSU rRNA coding region. Twelve D-domains within the LSU rDNA were put together into 1,879 bp (44.4% G+C), and cores into 1514 bp (42.8% G+C). The core sequence was significantly different (0.0867 of genetic distance, 91% sequence similarity) in comparison withProrocentrum micans (GenBank access. no. X16108). The D2 region was the longest in length (300 bp) and highly variable among the 12 D-domains. In a phylogenetic analysis using complete LSU rDNA sequences of a variety of phytoplankton,A tamarense was clearly separated with high resolution against other species. The result suggests that the sequence may resolve the taxonomic ambiguities ofAlexandrium genus, particularly of the tamarensis complex.  相似文献   
104.
江苏岸外辐射沙脊群东沙稳定性研究   总被引:8,自引:0,他引:8  
陈君  王义刚  张忍顺  林祥 《海洋工程》2007,25(1):105-113
东沙是江苏岸外辐射沙脊群中的第二大沙洲,具有独特的地形地貌和水动力条件,对它进行稳定性研究为揭示整个辐射沙洲及其邻近岸滩的动态演变都非常有益。通过利用多年遥感卫片资料、1998年取得的现场水文泥沙观测资料和东沙滩面表层沉积物资料等,对东沙的地形地貌特征、沉积特征和东沙两侧潮汐通道的水流泥沙特征等进行了详细分析。研究结果表明,东沙的沙脊偏于西侧,西侧滩面较窄、高程较高且岸线较为顺直,东侧滩面较宽、高程较低且岸线较为破碎;西洋和陈家坞槽均处于冲刷状态,净输沙的主要方向为输向槽外或输向条子泥;东沙近三十年来面积有所缩小且有外围向中央收缩的趋势,尤其以向东、向南方向的迁移最为明显。  相似文献   
105.
以 CG2 0潜山为例 ,从建立地质模型入手 ,包括地层模型、构造模型、储集模型、储盖组合模型、速度模型等 ,认识到各套地层分布和储层物性的差异均与地震响应密切相关 ,因此可以利用地震波的信息 ,预测潜山储层的发育及分布情况。在对 CG2 0潜山进行精细全三维构造解释的基础上 ,探讨性地应用了测井约束反演、吸收系数、相干分析及三维模式识别等技术 ,对潜山储层进行了预测 ,从而提高了潜山勘探的效益 ,并为类似断阶型潜山带的勘探提供了成功的经验 ,具有一定的指导意义。  相似文献   
106.
江苏岸外条子泥二分水滩脊的沉积特征   总被引:3,自引:1,他引:3  
陈君  张忍顺 《海洋通报》2003,22(3):23-30
2000年1月16日在江苏岸外条子泥沙洲二分水滩脊选取三条断面,进行底质沉积物采样及滩面高程测量。共采集样品27个,对其用激光粒度仪进行粒度分析,发现沉积物的粒度参数、粒度组分及其分布均具有一定的变化规律,且与滩面高程变化具有很好的相关性。  相似文献   
107.
The effects of Prorocentrum donghaiense,Karenia mikimotoi,Alexandrium catenella,the causative species of Harmful Algal Blooms in the East China Sea,on the survival and growth of Neomysis awatschensis and Artemia salina were investigated.And the toxicity of eleven strains of Alexandrium----A.lusitanicum(AL-1)、A.minutum(AM-1)、A.spp.(A-K)、A.tamarense(ATHK,ATCI02,ATCI03,AT5-1,AT5-3,AT-6)、A.affine(AS-1,AC-1) to the two above organisms were compared. The results showed that P.donghaiense and K.mikimotoi had no adverse effect on the survival and growth of N.awatschensis and A.salina at 96h.However,the survival rate of N.awatschensis and A.salina declined linearly with the increasing density of A.catenella,and the 96h LC50 for N.awatschensis and A.salina was 4500 and 460 cells/mL,respectively, Five strains of Alexandrium----A.spp,A.lusitanicum (AL-1),A.tamarense(AT5-3,AT-6) and A.affine (AS-1)at the density of 4000cells/mL and 96h had no adverse impacts on N.awatschensis. But other six strains of Alexandrium a.Tamarense(AT5-1,ATHK,ATCI02,ATCI03),A.affine(AC-1) and A.minutum(AM-1)decreased the survival fate of N.awatschensis significantly. Two strains of Alexandrium----A.lusitanicum(AL-1) and A.tamarense(AT-6),at the density of 500cells/mL. had no adverse effects on A.salina in 96h;while the other Alexandrium strains all had adverse effeets on the survival of a.salina, A.salina could increase its length with the increasing density of P.donghaiense,K.mikimotoi and A.luxitanicum. The results indicate that P.donghaiense and K.mikimotoi have nio significant effect on the survival of crustaeean zoop lankton in a short period. But several Alexandrium specised/strains could influence the survival of crustacean zooplankton likely by non-PSP substances. A.salina is shown to be more sensitive than N.awatschensis as test organisms to harmful species.  相似文献   
108.
Oceanographic conditions off Central California were monitored by means of a series of 13 hydrographic cruises between February 1997 and January 1999, which measured water properties along an oceanographic section perpendicular to the California Coast. The 1997–98 El Niño event was defined by higher than normal sea levels at Monterey, which began in June 1997, peaked in November 1997, and returned to normal in March 1998. The warming took place in two distinct periods. During June and July 1997, the sea level increased as a result of stronger than normal coastal warming below 200 dbars and within 100 km of the coast, which was associated with poleward flow of saltier waters. During this period, deeper (400–1000 dbar) waters between 150–200 km from shore were also warmed and became more saline. Subsequently, sea level continued to rise through January 1998, mostly as a result of the warming above 200 dbars although, after a brief period of cooling in September 1997, waters below 200 dbar were also warmer than normal during this period. This winter warm anomaly was also coastally trapped, extending 200 km from shore and was accompanied by cooler and fresher water in the offshore California current. In March and April 1998, sea level dropped quickly to normal levels and inshore waters were fresher and warmer than the previous spring and flowed southward.The warming was consistent with equatorial forcing of Central California waters via propagation of Kelvin or coastally-trapped waves. The observed change in heat content associated with the 1997–98 El Niño was the same as that observed during the previous seasonal cycle. The warming and freshening events were similar to events observed during the 1957–58 and 1982–83 El Niños.  相似文献   
109.
A seamount chain with an approximately WNW trend is observed in the northeastern Ulleung Basin. It has been argued that these seamounts, including two islands called Ulleung and Dok islands, were formed by a hotspot process or by ridge related volcanism. Many geological and geophysical studies have been done for all the seamounts and islands in the chain except Anyongbok Seamount, which is close to the proposed spreading ridge. We first report morphological characteristics, sediment distribution patterns, and the crustal thickness of Anyongbok Seamount using multibeam bathymetry data, seismic reflection profiles, and 3D gravity modeling. The morphology of Anyongbok Seamount shows a cone shaped feature and is characterized by the development of many flank cones and flank rift zones. The estimated surface volume is about 60 km3, and implies that the seamount is smaller than the other seamounts in the chain. No sediments have been observed on the seamount except the lower slope, which is covered by more than 1,000 m of strata. The crustal structure obtained from a 3D gravity modeling (GFR = 3.11, SD 3.82 = mGal) suggests that the seamount was formed around the boundary of the Ulleung Plateau and the Ulleung Basin, and the estimated crustal thickness is about 20 km, which is a little thicker than other nearby seamounts distributed along the northeastern boundary of the Ulleung Basin. This significant crustal thickness also implies that Anyongbok Seamount might not be related to ridge volcanism.  相似文献   
110.
太平洋波高分布及变化规律研究   总被引:4,自引:0,他引:4  
使用 Topex/ Poseidon卫星高度计 1 992年 1 0月~ 1 998年 1 2月连续 75个月 ,2 30个重复周期的有效波高资料对南北太平洋的有效波高进行了统计 ,分析了太平洋有效波高的多年平均、多年各月平均和多年各季平均的空间分布特征和时间变化规律。结果表明 ,太平洋波高分布具有明显季节变化的规律 ,与太平洋的风速分布特征具有良好的对应关系  相似文献   
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