Glass inclusions in volcanic rocks in the Okinawa Trough back-arc basin:constraints on magma genesis and evolution

INTROOUcr1ONThe Okinawa Trough is a typical marginal back-arc basin, where its oPening began in rela-tively recent years* There is a great controversy about the origin of its initial magYna. haltand acid volcanic pumice make up the bimedal volcanism in the Okinawa Trough. MOSt of geol-ogists believed that the acid pumice was the preduct of extremely crystal fractionation of baseltInagTna, but the others argued that it should com from the melting of lower-crust. Som de-tailed petrolOgic…     

水中荧光计及其在海洋现场探测中的应用

本文描述了近几年来我们首次研制成功的３种类型的水中荧光计系统及其应用测量结果：１．用于水体混合扩散实验研究的水中荧光计，对罗丹明Ｂ浓度测量范围为１×１０－６～１×１０－１０ｇ／ｃｍ３；２．拖曳荧光计系统，能在２～８０ｍ水深内进行水平拖曳平稳地工作，拖曳速度为０～８ｋｎ，除检测罗丹明Ｂ外，还可检测无机悬浮物质的含量，检测范围为２～２０００ｍｇ／ｄｍ３；３．用于测量海中浮游植物体内叶绿素ａ浓度的水中荧光计，测量范围为１×１０－６～１×１０－９ｇ／ｃｍ３。用荧光法测量海中物质是近代新发展的一种简便、快速、灵敏度高、用途极其广泛的测量技术，有着重要的应用价值。     

Wave Decay and Its Characteristics in Surf Zone

In accordance with the similarity between breaking waves and hydraulic jumps, the expressions for estimating wave decay and wave energy dissipation in the surf zone are derived based on the fundamental equations of fluid mechanics. Using the numerical solution of cnoidal wave theory, the various kinematic properties of waves in the surf zone, including the relative wave crest height, wave energy, and radiation stress are discussed. The values calculated with the method proposed in this paper are in good agreement with the experimental data gained by other researchers. The present expressions can be used in the studies of sediment transport on gently sloping beaches, especially on muddy beaches.     

山东近海牙鲆(Paralichthys olivaceus)自然和养殖群体10个微卫星基因座位的遗传多态性分析

采用微卫星遗传标记技术对山东近海牙鲆自然群体和养殖群体的遗传多样性进行了研究。实验所用牙鲆于2003年5月分别采自山东近海和青岛胶南养鱼场，各20尾，取全血或肌肉组织，以酚-仿抽提方法提取基因组DNA，利用筛选获得的10对微卫星引物进行PCR扩增，反应产物经8％非变性聚丙烯酰胺凝胶电泳分离、EB显色，用ImageMasterl D Elite(Version 3．01)软件分析电泳结果，并计算了相应的遗传学参数。结果表明，在自然和养殖群体中，10个基因座位的等位基因平均数(α)分别为6．7和6．1，每个基因座位有效等位基因数(αe)分别为1．8—6．8和2．5—6．7，群体平均杂合度(H)分别为0．8120和0．7310；两个群体间的遗传相似性系数、遗传距离和基因分化系数为0．8558、0．1557和0．0558；自然群体内每个座位上的多态信息含量(PIC)为0．59—0．84、个体识别率(DP)为0．54—0．86、非父排除率(PPE)为0．41—0．72，其累积个体识别率和非父排除率均达到0．9999，表明所选座位属中高识别力的遗传标记，可以将它们应用于今后牙鲆雌核发育群体的遗传变异分析以及进一步的遗传育种的研究中。     

The Agulhas Ridge, South Atlantic: The Peculiar Structure of a Fracture Zone

The Agulhas Ridge is a prominent topographic feature that parallels the Agulhas-Falkland Fracture Zone (AFFZ). Seismic reflection and wide angle/refraction data have led to the classification of this feature as a transverse ridge. Changes in spreading rate and direction associated with ridge jumps, combined with asymmetric spreading within the Agulhas Basin, modified the stress field across the fracture zone. Moreover, passing the Agulhas Ridge’s location between 80 and 69 Ma, the Bouvet and Shona Hotspots may have supplied excess material to this part of the AFFZ thus altering the ridge’s structure. The low crustal velocities and overthickened crust of the northern Agulhas Ridge segment indicate a possible continental affinity that suggests it may be formed by a small continental sliver, which was severed off the Maurice Ewing Bank during the opening of the South Atlantic. In early Oligocene times the Agulhas Ridge was tectono-magmatically reactivated, as documented by the presence of basement highs disturbing and disrupting the sedimentary column in the Cape Basin. We consider the Discovery Hotspot, which distributes plume material southwards across the AAFZ, as a source for the magmatic material.     

河口涨落潮槽水动力特征及河槽类型判定

在前人对河口冲刷槽研究的基础上,选择长江口南支、新桥水道、南小泓和南港主槽作为典型涨、落潮槽研究对象,以2001年洪季和2003年枯季实测资料为根据,比较分析了长江口涨落潮槽的水流、泥沙、优势流和优势沙等动力特征,结果表明用单一因子分析河槽性质不够全面.提出了一个(无量纲因子)河槽类型系数(λ)来综合表述河槽的多种水文泥沙特征,可以较全面地用多个影响因子来合理地判断河槽类型.     

Characteristics of Scour and Deposition in Front of Breakwaters Under Irregular Broken Clapotis

First the scour and deposition patterns of the sandy seabed in front of a vertical breakwater under the action of irregular broken clapotis are investigated experimentally and classified into five types: scour type Ⅰ , scour type Ⅱ, scour type Ⅲ, deposition type Ⅰ, and deposition type Ⅱ . Secondly, the processes of formation of scour and deposition patterns are probed in comparison with those induced by regular broken clapotis and standing waves. Thirdly, the criteria for distinguishing scour and deposition patterns under irregular broken clapotis are presented.     

Variations in wave direction estimated using first and second order Fourier coefficients

In most design applications such as alignment of the berthing structure and breakwater alignment, it becomes necessary to determine the direction of design wave. There are two different approaches to determine wave direction. One involves the use of first order Fourier coefficients (mean wave direction) while the other uses second order Fourier coefficients (principal wave direction). Both the average wave direction over the entire frequency range (0.03–0.58 Hz) and the direction corresponding to the peak frequency are used in practice. In the present study, comparison is made on wave directions estimated based on first and second order Fourier coefficients using data collected at four locations in the west and east coasts of India. Study shows that at all locations, the mean and principal wave directions for frequencies ranging from 0.07 to 0.25 Hz (±0.5 times peak frequency) co-vary with a correlation coefficient of 0.99 but at lower and higher frequencies, difference between the parameters is large. Average difference between the mean wave direction at peak frequency and the average over the frequency related to spectral energy more than 20% of maximum value is less, around 13°. Study shows that average difference in the sea and swell directions is around 39°.     

Guidelines for navigation and overflight in the exclusive economic zone

Several significant international incidents in Asian exclusive economic zones (EEZs) have underscored the ambiguity and lack of agreement regarding the regime governing foreign military activities in coastal States’ EEZs. A group of senior officials and analysts participated in their personal capacities in a dialogue from 2002–2005 that discussed the issues with a view to improving mutual understanding of the regime and finding areas of agreement. The Tokyo meeting in September 2005 reached consensus on some voluntary, non-binding guidelines that are presented here. The guidelines are based selectively on the 1982 UNCLOS, State practice and emerging ‘soft’ law, and attempt to balance the interests of coastal States and user States. It is hoped that they may serve as the basis for discussion and eventual agreements between governments.