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81.
长6油层组储集砂岩主要为岩屑长石砂岩,粒度较细,分选中等偏差,填隙物主要为碳酸盐矿物和粘土矿物。砂岩的物质组成影响着其储层性能,储层物性随着石英含量的增加而变好,而随着岩屑含量的增加而变差。砂岩中长石的溶蚀作用是改善储层物性的关键因素。填隙物的含量越大,则孔隙喉道堵塞和充填的程度增加,导致储层物性变差。  相似文献   
82.
松辽盆地及外围上古生界油气资源战略选区研究进展   总被引:4,自引:0,他引:4  
松辽盆地及外围上古生界油气地质研究和勘探程度均较低,资源前景广阔。通过油气资源战略选区工作,第一阶段针对石炭系和二叠系,开展前期的盆地评价和战略选区,实施少量的地球物理勘查和科探井工程等实物工作量,围绕古生界构造演化、地层和岩相古地理、有效烃源岩以及可能的油气远景区等方面,研究盆地深部晚古生代盆地性质,揭示在新的构造体制下不同构造阶段盆地的演化规律,基本查明松辽盆地及外围上古生界的分布、厚度、岩性、岩相特征,开展烃源岩的时效性、原型盆地恢复与重建、构造演化历史和有利成藏条件研究,提出有利远景区,供企业进一步勘探验证,这对发展和创新石油地质理论,实现松辽盆地及外围油气勘探的可持续发展,具有重要的经济社会意义。  相似文献   
83.
吉林油田乾146区块经多年开采,已经进入高含水、高采出阶段。通过储层流动单元研究,运用多参数模糊聚类方法将该区高台子油层由好至差划分为A、B、C、D、E 5类储层流动单元。查明了区内主要目的层系各含油小层的储层流动单元发育特征:40、39小层主要发育A、B类优质储层流动单元,42、41、38小层则以C、D、E类储层流动单元为主,各小层储层流动单元类型及展布与初始产能吻合度较高,表明储层流动单元类型的差异是控制本区油气分布的重要因素之一。综合油藏地质特征及油田开发动态数据,对各储层流动单元的注采渗流体系进行了深入剖析,归纳总结出乾146区块高台子油层XII砂组中剩余油分布的5条规律,据此在剩余油分布预测区部署了1口扩边井和2口老区加密井,投产后分别获得了11.2t/d、5.5t/d和8.6t/d的初始产能。  相似文献   
84.
Rudders of large container ships are easily affected by cavitation, which is well known to be induced by significant axial flows behind a propeller and discontinuities in the rudder. Among several methods to prevent or reduce the cavitation erosion occurred in the rudder, painting is gaining a lot of attention because it can be employed easily and cheaply. To conduct erosion tests properly, the simulation of heavily erosive cavitation is necessary. This can be generated using an inclined propeller dynamometer in the medium-size cavitation tunnel of MOERI (Maritime & Ocean Engineering Research Institute). The inclined shaft of the propeller creates strong cavitation, which occurs around the root of the propeller blade. This cavitation creates impacts through the collapsing process that are very severe, and are useful for realistic and efficient cavitation erosion tests. In the present study, the newly developed cavitation erosion test method is successfully employed to evaluate marine coatings that is mainly composed of epoxy elastomer or silicone polymer material. Silicone polymer-type paint B was found to have three times larger endurance than epoxy elastomer-type paint A.  相似文献   
85.
This paper examines key factors used in protecting the migratory North Atlantic right whale within the context of a marine protected area (MPA) system, using the Grand Manan Whale Conservation Area, in New Brunswick Canada, as a case study example. Designated as a conservation area in 1993, before the Oceans Act came into effect, the Grand Manan conservation area currently does not form part of the Canadian network of MPAs. Given the possibility that MPA designation may occur, the paper examines factors that should be considered in meeting International Union for Conservation of Nature (IUCN) MPA design criteria and IUCN evaluation model requirements. An MPA evaluation framework based on an IUCN evaluation model (Hockings et al., 2000 [1]) is designed to assess the effectiveness of an MPA in protecting a migratory right whale. Case study results indicate that current management and research activities for the Grand Manan conservation area address most governance, biophysical and socio-economic issues under an IUCN evaluation framework. On a site basis, it is recommended that the Grand Manan conservation area be designated as a component of the Canadian network of MPAs and that regulations be developed and implemented under the Species at Risk Act to clearly define activities considered damaging or destructive to right whale critical habitat. Recommendations also suggest the preparation of a combined site management-action plan for the Grand Manan conservation area indicating how activities specified in North Atlantic Right Whale Recovery Strategy will be implemented locally. On a regional and international basis, recommendations call for an internationally coordinated and integrated approach to right whale protection within the context of a network of designated critical habitat areas. Recommended activities include: continued Canadian participation in cross-border research and actions to mitigate threats to the right whales over their migratory range; development of a regional right whale management and monitoring strategy; and designation of additional critical habitats in national/international waters. It is further recommended that the evaluation framework developed by this paper be used as a model in assessing the conservation and management effectiveness of MPAs protecting other migratory marine species.  相似文献   
86.
Islands are often considered to be a priority for conservation, because of their relatively high levels of biodiversity and their vulnerability to a range of natural and anthropogenic threats. However, the capacity of islands to conserve and manage biodiversity may depend upon their governance structures. Many island states are affiliated to other countries through an ‘overseas territory’ status, which may provide them with access to resources and support mechanisms, but which may also influence the capacity for local-scale management of environmental issues. The United Kingdom has 12 island Overseas Territories (UKOTs), most of which support biodiversity of high conservation concern. This study investigates perceptions of current and future threats to marine ecosystems and constraints to environmental protection on the six Caribbean UKOTs, through semi-structured interviews with officials from UK and UKOT government departments and non-governmental organisations. Coastal development, pollution and over-fishing were perceived as threats of most concern for the next decade, but climate change was perceived as by far the greatest future threat to the islands' marine ecosystems. However, a series of common institutional limitations that currently constrain mitigation and conservation efforts were also identified, including insufficient personnel and financial support, a lack of long-term, sustainable projects for persistent environmental problems and inadequate environmental legislation. These findings highlight the need for regional cooperation and capacity-building throughout the Caribbean and a more concerted approach to an UKOT environmental management by the UK and UKOTs' governments.  相似文献   
87.
The Padu system of South Asia has received growing attention as an example of customary marine tenure that has survived despite rapid development and change throughout the region’s fisheries. This paper describes the Padu system as it functions at Pulicat lagoon, India, where it has enjoyed decades of legitimacy amongst its members, and has contributed to sustainable fishing. Recently, however, the Padu system has become unstable, driven by pressures of an expanding fishing population, reduced access to fishing grounds and a growing ‘shared poverty’. In spite of this, fisher loyalty to uphold the Padu system remains strong. This raises questions about the broader social, political and cultural meanings of Padu, which extend beyond access to a lucrative fishery. The paper highlights a trade-off between the benefits received through Padu membership at a societal level through collective action, and the individual costs of partaking in ‘shared poverty’, which is inherently distributed unequally amongst fishing families. The paper concludes with a discussion on the future of the Padu system in Pulicat, drawing from evolutionary pathways of other Padu systems in the region. It is suggested that, in the Pulicat case, the high social values attributed to the Padu system, alongside complex power structures, may hinder institutional adaptation.  相似文献   
88.
This paper reviews the evidence of the impacts of marine management interventions on human development and well-being reported in marine management literature in the past two decades. Documents dealing with fisheries, aquaculture, marine conservation and coastal zone management are assessed in terms of the methodologies used, the human development dimensions considered, and the results reported. The choice of dimensions for defining human development in this literature is contrasted with proposals from the literature on the capability and human development approaches. Possible areas for future research are discussed.  相似文献   
89.
Responses of governance systems to change in coastal and marine ecosystems vary from country to country around the globe. Lessons can be learned from country specific case studies, as national governments strive to adapt and respond to issues of concern. This short paper highlights the benefits of a country-specific, special edition of Marine Policy, with a focus on Ireland. Despite the uniqueness of socio-ecological setting, many of the issues faced by policy makers in Ireland, such as the reconciliation of economic development and conservation needs, are shared elsewhere. This special edition was produced at the end of the ‘Celtic Tiger’ in Ireland. As a result, it reflects an era when economic development was very much a priority. The same period represented an unparalleled investment in marine science since the foundation of the State in 1922. Despite this, the papers in the Special Edition point to varying degrees of progress in policy integration and implementation. Papers covering a range of sectors (fisheries, ocean energy, conservation and fisheries) and disciplines (economics, science and management) will be of interest to academics, policy makers, students and practitioners of marine policy.  相似文献   
90.
海洋沉积地质过程模拟:性质与问题及前景   总被引:3,自引:0,他引:3  
探讨了海洋沉积地质数值模拟的功能问题.地球科学研究以正演方法(以数值模拟为代表)和反演方法(以地层记录分析为代表)的结合为特征.数值模拟作为一种重要的研究工具,具有获得过程和机理分析结果、形成工作假说、指导现场观测和采样的作用.与此同时,在正反演交融中模型本身也得到了提高和完善.在海洋沉积地质领域,数值模拟在沉积物输运...  相似文献   
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