衡阳市湘江水污染特征及其治理

本文探讨了衡阳市湘江水中主要污染物的来源,分布,运移特征及河床沉积物的污染特征,进而评价了其水质并提出治理措施。     

胜利海上埕岛油田下古生界潜山高产因素分析

埕岛油田是我国浅海－极海海域发现的第一个大型整流油气田,四周环凹,油源条件十分优越,全区可划分为西排山,中排山,东排山三个潜山带构造单元,油气运移通道主要是断裂和风化壳不整合面,区域盖层发育良好,储集条件是油气富集高产控制因素,纵向上潜山带储层主要集中在潜山的风化壳;平面上主要沿断层分布,沿断层发育的奥陶系在潜山是本区古生办潜山勘探的最有利目标。     

“干化蒸发”与“回灌重溶”——对鄂尔多斯盆地东部奥陶系蒸发岩成因的新认识

鄂尔多斯盆地东部奥陶系发育巨厚的蒸发岩地层,已有不少学者对其成因提出了不同的假设。本文通过对该区蒸发岩微相分布规律、剖面结构及地球化学等特征的分析,提出该区蒸发岩形成于成盐盆地与外海周期性隔绝的“干化蒸发”条件下的新认识。首次提出用“回灌重溶”机制来解释厚层石盐岩中的泥质薄夹层的成因、各种石盐岩颜色的成因及蒸发岩剖面中缺乏干化蒸发晚期阶段的钾镁盐层的原因,并由此提出 “溶积层”的概念。微相分析表明,在形成蒸发岩的盐坳盆地东部的水下古地形隆起上,发育有堤坝状的礁或生物丘等生物建隆,其在地形上的隆起构成了盐坳盆地与外海的障壁,在海平面下降期间可使盐坳与外海完全隔绝而进入干化蒸发阶段,从而形成了石盐沉积;由海平面上升所造成的突发性海水回灌事件又使先成的石盐层部分溶解（回灌重溶）,并由于不溶残余物的富集成层（溶积层）而阻止了下伏石盐层的进一步溶解。这是该区蒸发岩地层中缺少典型干化证据的主要原因。本区奥陶系马家沟组碳酸盐岩与蒸发岩间互分布的地层层序结构特征,主要受控于区域海平面变化旋回,碳酸盐岩主要形成于海侵期和高水位期,蒸发岩则主要形成于低水位期。     

Numerical Simulation of Wave Interaction with Perforated Caisson Breakwaters

1 .ＩｎｔｒｏｄｕｃｔｉｏｎＴｒｅｍｅｎｄｏｕｓｄｅｖｅｌｏｐｍｅｎｔｏｆｉｎｔｅｒｎａｔｉｏｎａｌｔｒａｄｅａｎｄｓｅａｔｒａｎｓｐｏｒｔａｔｉｏｎｈａｓｔａｋｅｎｐｌａｃｅｓｉｎｃｅｔｈｅ1 980ｓ.Ｄｕｒｉｎｇｔｈｅｓａｍｅｐｅｒｉｏｄｏｆｔｉｍｅ ,ｈａｒｂｏｒｔｒａｎｓｐｏｒｔａｔｉｏｎｉｎｃｒｅａｓｅｄｍａｒｋｅｄｌｙ ,ｒｅｓｕｌｔｉｎｇｉｎｔｈｅｄｅ ｔｅｒｉｏｒａｔｉｏｎｏｆｗａｖｅｃｏｎｄｉｔｉｏｎｓｉｎｈａｒｂｏｒｓ .Ｒｅｄｕｃｉｎｇｗａｖｅｄａｍａｇｅｔｏｐｏｒｔａｎｄｍａｒｉｎｅ…     

Spatio-temporal variations in reproductive patterns and population structure of Pasiphaea multidentata (Decapoda: Caridea) in the Blanes canyon and adjacent margin, North-western Mediterranean Sea

Pasiphaea multidentata is a deep‐water caridean shrimp fished in the Mediterranean in association with the commercially exploited red‐shrimp Aristeus antennatus. A previous study describes seasonality in the reproductive pattern of P. multidentata using external morphological parametres. This study assesses the spatio‐temporal variations in the population structure, sex ratio, ovary cycle and gametogenesis of P. multidentata from three different fishing grounds in the Blanes canyon and adjacent margin (North‐western Mediterranean) over an annual cycle. The oogenetic pattern of this species is typical of a caridean shrimp. There is a pool of previtellogenic oocytes at all times that develop from the periphery of the gonad towards the centre during maturation. Previtellogenic oocytes grow to approximately 200 μm before undergoing vitellogenesis. The vitellogenic oocytes are surrounded by a monolayer of accessory cells. The maximum size observed for a mature oocyte was 1420 μm. The oocyte‐size distribution confirmed the seasonal reproductive pattern of this species; in winter, the ovaries contained mainly previtellogenic oocytes, some of which start maturing in spring, resulting in a slightly bimodal distribution. In summer, the vitellogenic oocytes reach approximately 1000 μm and in late autumn the ovaries are fully mature and ready to spawn. There were no significant differences in the reproductive and population structure patterns of P. multidentata among the three sites, suggesting that the population’s distribution is not affected by the geomorphology of the area, in particular the presence of the canyon. The populations are dominated by females at all sites and all seasons, with the arrival of juveniles in spring. The seasonal variations in the reproduction and recruitment of P. multidentata and the lack of spatial segregation within the population are discussed in terms of the species’ known biology, the effects of canyons in energy supply to the deep‐sea floor and the relationships of this species with the red‐shrimp A. antennatus.     

Coating Protection for Production Facilities of Offshore Oil Fields

- This paper describes coating protection of production facilities of offshore oil fields based on the practice of development of Bohai Offshore Oil Field, with focus laid on the selection of coating systems, surface preparation, coating application, as well as coating inspection for four types of major production facilities.     

34万吨级FPSO的中横剖面优化设计

以中横剖面的面积最小为目标函数，应用自适应步长随机搜索法，对34万吨级FPSO中横剖面进行了优化设计，并将规范设计结果和优化设计结果进行了比较，优化效果较好。     

Unified Water Gravity Wave Theory and Improved Linear Wave

- Based on Least Square Method, this paper presents variational principle for handling various water gravity wave theories and the unified water gravity wave theory was given. By using this variational principle of unified water wave theory, two kinds of improved linear waves were derived. The first one uses the same boundary conditions which were applied to derive 5-order Stokes wave. The second one uses the accurate boundary conditions (Eqs. 11 and 12). The two improved linear waves were compared with the existing linear wave.     

Underwater Explosion Technology for Offshore Engineering Applications

- This article briefs how to improve the holding power of a drilling vessel's anchor and to remove those unreasonable structures by such a technology - underwater-explosion technology. The article gives details of the structure, characteristics and applications of a rocket-launched anchor; as well as the principle, properties, applications of directional explosion cutting.     

Equivalent Simplifying of Tower Structure and Its Application in Overall Analysis of Offshore Platform

Based on some mechanical principles, this paper presents a new way for simplifying the tower structure on the platform, i. e., substituting the three-dimensional tower structure by using beam elements. For the overall analysis of offshore platform, this method can not only save man- power and computer time, but also get better results. This paper introduces the equivalent-simplifying method and its application in engineering.