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141.
Yanmei Wu Peter D. Clift Jiabiao Li Shaoru Yin Yinxia Fang 《International Geology Review》2020,62(7-8):970-987
ABSTRACT We calculated the sedimentary budget of the Northwest Sub-basin (NWSB), South China Sea for different geological times based on interpretations of four multichannel seismic profiles across the basin with constraints from International Ocean Discovery Program (IODP) Expeditions 367 and 368 drilling results. Sedimentation was generally dominated by regional tectonic events and climate change, but complicated by local tectonic events and geographic position, which resulted in a specific sedimentary budget in the NWSB compared with other marginal basins and the Southwest Sub-basin. The sedimentation rate was relatively low following the opening of the NWSB but increased gradually during the Middle Miocene, corresponding to the uplift of the Tibetan Plateau and the Asian monsoon. It reached its peak in the Late Miocene, corresponding to uplift of the Dongsha Island region that caused intensive bypass of eroded sediments from the Baiyun Sag into the abyssal basin, and reduced again during the Pliocene because of sediment storage on the wide northern continental shelf area compared to the abyssal basin during a period of high-stand sea level. Increase in sedimentation during the Pleistocene suggests that continental erosion and sediment transport to the abyssal basin were enhanced by an intensified Asian summer monsoon and glacial-interglacial climate fluctuations. Since the opening of the NWSB, the primary sediment provenance has been from southern China, with minor contributions from the Red River, Hainan Island, as well as local uplifts on the continental shelf. 相似文献
142.
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
143.
Transnational development networks: bringing development and postcolonial approaches into dialogue 总被引:2,自引:0,他引:2
COLIN MCFARLANE 《The Geographical journal》2006,172(1):35-49
This paper explores some of the ways in which a dialogue between development and postcolonial scholarship might contribute to the theorizing of transnational networks in contemporary development. It does so through consideration of three inter-related themes: epistemologies, spatialities and ethico-politics. The discussion of epistemologies points to the potential benefit in reworking the analysis of the relationship between structure and agency in networks, whereas the discussion of spatialities focuses attention on the interface between the global and the local. Dialogue between development and postcolonial approaches also creates space for considering the politics and ethics of transnational development networks. In particular, this discussion prompts challenges around how to ethically research subaltern knowledge in transnational development networks, including how to trace the translation and redeployment of subaltern knowledge through networks. Consideration of these themes highlights not just overlaps and disjunctures between development and postcolonial approaches, but opportunities for further dialogue and future research on transnational development networks. To illustrate the points made in the paper, examples are drawn from Slum/Shack Dwellers International (SDI), a transnational network of civil society organizations working with urban poverty. 相似文献
144.
Champ MA 《Marine pollution bulletin》2002,44(12):1327-1335
The proposed MTB is a process to expedite the implementation of international standards and regulations, and the subsequent testing, certification, and regulatory approval of new ballast water treatment ("control") technologies. This would expedite their acceptance in the global marketplace and reduce risks of shipowners following international regulation. The cost to test and evaluate and certify new ballast water treatment technologies for the global marketplace has been estimated to be less than US $1 per day per ship. It is time for the shipping industry, national regulatory bodies, and IMO to endorse the concept of the MTB and for the shipping industry to support a proactive cost-saving solution for sustainable shipping and protecting the environment from unwanted invasions of aquatic species with their potential negative impacts. 相似文献
145.
根据IGRF计算1995~2000年中国及邻区地磁长期变化 总被引:2,自引:0,他引:2
根据最新的第七代国际地磁参考场,计算并绘制1995~2000年中国及邻区地磁长期变化图,分析了长期变化的空间变化。 相似文献
146.
Spain is a relatively large European country (ca. 500,000 km2) with extensive semiarid areas in which there exists a large number of good aquifers. In some areas, these aquifers are intensively
developed and are the most important sources of fresh water. Nevertheless, groundwater development and protection has rarely
been duly considered by the Spanish Water Administration, despite the pressure to remedy this situation by various groups
of experts, some of them members of the Water Administration. The Spanish Committee of the International Association of Hydrogeologists
(IAH) has been very active during the last decade in promoting activities to spread groundwater science, technology, and management
in Spain and outside, mostly in Latin America, and in trying to orient water policy toward issues of groundwater. These activities
include mainly the organization of technical and scientific meetings on current topics such as groundwater in the new Water
Act, overexploitation, groundwater in water-resources planning, groundwater pollution, natural-recharge estimation and others.
The impact of these activities on the recent water policy of Spain seems significant, and the experience gained may be applicable
to other countries.
Received, February 1997 · Revised, July 1997 · Accepted, July 1997 相似文献
147.
Shiang-Kueen Hsu 《Hydrogeology Journal》1998,6(3):405-415
In Taiwan, rapid economic growth, rising standards of living, and an altered societal structure have in recent years put
severe demands on water supplies. Because of its stable quantity and quality, groundwater has long been a reliable source
of water for domestic, agricultural, and industrial users, but the establishment of a management program that integrates groundwater
and surface-water use has been hampered by the lack of groundwater data. In 1992, the Department of Water Resources (DWR)
initiated a program entitled "Groundwater Monitoring Network Plan in Taiwan." Under this program, basic groundwater data,
including water-level and water-quality data, are being collected, and a reliable database is being established for the purpose
of managing total water resources. This paper introduces the goals, implementation stages, and scope of that plan. The plan
calls for constructing 517 hydrogeologic survey stations and 990 groundwater monitoring wells within 17 years. Under this
program, water-level fluctuations are continuously monitored, whereas water-quality samples are taken for analysis only at
the initial drilling stage and, subsequently, at the time when a monitoring well is being serviced. In 1996, the DWR and the
Water Resources Planning Commission were merged to form today's Water Resources Bureau.
Received, July 1997 · Revised, February 1998 · Accepted, January 1998 相似文献
148.
当前我国港口发展条件分析:兼论上海国际航运中心 总被引:27,自引:4,他引:23
本文根据我国社会主义市场经济体制及国际上船舶大型化与海洋货运集装箱化趋势,详细讨论了当前和21世纪初我国港口发展条件。认为社会、经济条件及人为作用对我国港口发展将起来越来越大的作用,传统的“以港兴市”概念已不尽适用。建设上海国际航运中心是国港口建设中的一件大事。上海国际航运中心将以组合港形式组建,包括一个中心港,即上海港,两个次中心港,即北仑港和太仑港,以及若干主要的支线港和喂给港。各港应合理分 相似文献
149.
90年代发展中国家国际资本流入的新特点及其影响 总被引:1,自引:1,他引:0
从1992年起,流向发展中国家的证券资本以较大的优势超过了国际直接投资。在全球经济一体化、金融市场自由化和国际化的背景下,国际资本跨国流动呈现出规模巨大化、运作方式机构化、流动形式多样化的特点。庞大证券资本的注入在给新兴市场国家带来益处的同时,也可能造成伤害,这一点在墨西哥和东南亚金融危机中已经得到证实。因此防范和化解国际资本的流入所带来的金融风险,是新兴市场国家当前所面临的严峻课题。 相似文献
150.
Thomas A. Wikle 《The Professional geographer》1995,47(1):41-48
This county-level study examines the locational concentrations of membership in a sample of national environmental organizations. Maps of location quotients indicate distinct regions of high and low membership concentrations, with membership most concentrated in the Northeast, West, and Rocky Mountain states. The results may be helpful in identifying general patterns of environmental concern in different U.S. regions. 相似文献