沙捞越盆地的盆地类型分析     

马良涛  赵聪会 《海洋地质前沿》2014,(2):27-32

针对沙捞越盆地盆地类型的不同观点,通过盆地区域构造背景、构造演化阶段、构造沉降曲线的分析以及构造地质事件的恢复,得到以下认识:①盆地的构造演化可划分为晚白垩世—晚始新世,拉让洋壳向婆罗洲基底俯冲,并在婆罗洲中部形成火山岛弧的俯冲增生期;渐新世—早中新世,拉让洋壳俯冲消减完毕,路科尼亚地块与婆罗洲碰撞,并俯冲于婆罗洲基底之下,形成周缘前陆盆地的前陆盆地期;中中新世至今,南中国海开启、婆罗洲碰撞抬升引起盆地稳定沉降的被动边缘期3个阶段。②盆地所选井的构造沉降曲线具有早期缓慢沉降、晚期快速沉降这一前陆盆地的典型特征。③盆地构造地质事件复原图表明,盆地晚期处于被动大陆边缘构造背景。由此,认为沙捞越盆地为复合型盆地,即早期为前陆盆地,晚期则转化为大陆边缘型盆地。  相似文献   

几种经典海洋环境噪声谱分析   总被引：1，自引：0，他引：1  

车永刚  张宁川  赵宝庆 《海洋测绘》2014,34(5):46-49

目前风关海洋环境噪声实验研究结果较多,其中较为经典的是Knudsen谱、Wenz谱、Piggott谱、Crouch谱,以及风速与噪声谱级的对数关系等。对这几种经典的海洋环境噪声谱进行了概述,分析了其数据来源,并对Wenz谱、Piggott谱和Crouch谱进行了比较,探究了其差异产生的原因,并给出了不同情况下进行风关海洋环境噪声估计时的参考建议。  相似文献   

中国南海表层沉积硅藻的分布及其与环境关系探讨          下载免费PDF全文

孙美琴  蓝东兆  王遹其  薛蕾 《海洋科学进展》2014,32(4)

通过对中国南海62个站位表层沉积硅藻的分析,查明研究海区硅藻的种类组成及分布特点。共鉴定到硅藻56属的235个种(包括变种和变型),以热性外洋种为优势,伴有一定量的近岸广布种。总体上,南海硅藻丰度变化呈现从陆架向陆坡至海盆递增的趋势。根据表层沉积硅藻中具有指示意义的硅藻种的分布和生态变化,划分6个硅藻组合带,各组合分别反映不同的海洋环境,其分布主要受到海洋环流的影响,表现为黑潮暖流、印度洋暖水的入侵以及沿岸流对南海表层沉积硅藻分布的影响。与南海相邻海区硅藻种类比较结果表明,研究海区表层沉积硅藻种类组成与临近的菲律宾海域相似程度最大,其次是中国东海海域、太平洋东北部海域。  相似文献   

船载ADCP资料处理          下载免费PDF全文

吴云帆  吴中鼎  李占桥 《海洋测绘》2014,34(6):36-39,42

通过对大量走航ADCP观测资料的分析,提出一整套的ADCP资料质量控制和预处理方法,并对提出的ADCP"基准流速控制"的处理方法与传统的"选取参考层法"进行了比较,证明此方法不但可有效提高ADCP资料的处理精度,并可提高资料的处理效率,减少人为的干预因素。  相似文献   

海洋声学调查数据处理系统的实现及关键技术          下载免费PDF全文

邓玉芬  孙磊  王川 《海洋测绘》2014,(2):69-71

针对目前我国海洋水声环境调查需求,结合国内现有的技术条件和现有的处理方法、原理,详述了海洋声学调查数据处理系统的实现途径及关键技术的解决,该系统软件满足我国目前海洋调查的需求,提高了海洋环境数据处理的自动化、数字化和信息化程度。  相似文献   

Land consolidation：An indispensable way of spa-tial restructuring in rural China     

LONG Hualou 《地理学报》2014,24(2):211-225

The implementation of new type industrialization and urbanization and agricultural modernization strategies lacks of a major hand grip and spatial supporting platform,due to long-term existed "dual-track" structure of rural-urban development in China as well as unstable rural development institution and mechanism. It is necessary to restructure rural production,living and ecological space by carrying out land consolidation,so as to establish a new platform for building new countryside and realizing urban-rural integration development in China. This paper develops the concept and connotation of rural spatial restructuring. Basing on the effects analysis of industrialization and urbanization on rural production,living and ecological space,the mechanism of pushing forward rural spatial restructuring by carrying out land consolidation is probed. A conceptualization of the models of rural production,living and ecological spatial restructuring is analyzed combining with agricultural land consolidation,hollowed villages consolidation and industrial and mining land consolidation. Finally,the author argues that a "bottom-up" restructuring strategy accompanied by a few "top-down" elements is helpful for smoothly pushing forward rural spatial restructuring in China. In addition,the optimization and restructuring of rural production,living and ecological space will rely on the innovations of regional engineering technology,policy and mechanism,and mode of rural land consolidation,and more attentions should be paid to rural space,the foundation base and platform for realizing urban-rural integration development.  相似文献   

A study of transport and impact strength of Fukushima nuclear pollutants in the north pacific surface     

FU Hongli  LI Wei  ZHANG Xuefeng  HAN Guijun  WANG Xidong  WU Xinrong  and ZHANG Lianxin 《中国海洋大学学报(英文版)》2014,13(2):183-190

Based on the statistics of surface drifter data of 1979–2011 and the simulation of nuclear pollutant particulate movements simulated using high quality ocean reanalysis surface current dataset, the transport pathways and impact strength of Fukushima nuclear pollutants in the North Pacific have been estimated. The particulates are used to increase the sampling size and enhance the representativeness of statistical results. The trajectories of the drifters and particulates are first examined to identify typical drifting pathways. The results show that there are three types of transport paths for nuclear pollutants at the surface: 1) most pollutant particles move eastward and are carried by the Kuroshio and Kuroshio-extension currents and reach the east side of the North Pacific after about 3.2–3.9 years; 2) some particles travel with the subtropical circulation branch and reach the east coast of China after about 1.6 years according to one drifter trajectory and about 3.6 years according to particulate trajectories; 3) a little of them travel with local, small scale circulations and reach the east coast of China after about 1.3–1.8 years. Based on the particulates, the impact strength of nuclear pollutants at these time scales can be estimated according to the temporal variations of relative concentration combined with the radioactive decay rate. For example, Cesium-137, carried by the strong North Pacific current, mainly accumulates in the eastern North Pacific and its impact strength is 4% of the initial level at the originating Fukushima area after 4 years. Due to local eddies, Cesium-137 in the western North Pacific is 1% of the initial pollutant level after 1.5 years and continuously increases to 3% after 4 years. The vertical movement of radioactive pollutants is not taken into account in the present study, and the estimation accuracy would be improved by considering three-dimensional flows.  相似文献   

Transition from the southern mode of the mei-yu front cloud system to other leading modes     

QIN Danyu  LI Bo  HUANG Yong 《大气科学进展》2014,31(4):948-961

Based on normalized six-hourly black body temperature （TBB） data of three geostationary meteorological satellites,the leading modes of the mei-yu cloud system between 1998 and 2008 were extracted by the Empirical Orthogonal Function （EOF） method,and the transition processes from the first typical leading mode to other leading modes were discussed and compared.The analysis shows that,when the southern mode （EOF1） transforms to the northeastern mode （EOF3）,in the mid-troposphere,a low trough develops and moves southeastward over central and eastern China.The circulation pattern is characterized by two highs and one low in the lower troposphere.A belt of low pressure is sandwiched between the weak high over central and western China and the strong western North Pacific subtropical high （WNPSH）.Cold air moves southward along the northerly flow behind the low,and meets the warm and moist air between the WNPSH and the forepart of the low trough,which leads to continuous convection.At the same time,the central extent of the WNPSH increases while its ridge extends westward.In addition,transitions from the southern mode to the dual centers mode and the tropical-low-influenced mode were found to be atypical,and so no common points could be concluded.Furthermore,the choice of threshold value can affect the number of samples discussed.  相似文献   

A Model Simulation of Future Oceanic Conditions along the British Columbia Continental Shelf. Part II: Results and Analyses     

M.G.G. Foreman  W. Callendar  D. Masson  J. Morrison  I. Fine 《大气与海洋》2014,52(1):20-38

An ocean circulation model for the British Columbia continental shelf is run with future initial conditions and forcing fields downscaled from the North American Regional Climate Change Assessment Program archive. Average seasonal sea surface temperatures for the period 2065 to 2078 are projected to increase by between 0.5° and 2.0°C with respect to analogous averages from 1995 to 2008. Seasonal sea surface salinities are projected to decrease by as much as 2.0 over the same period, though there are some regions where and periods when small increases are projected. Though stronger winter winds result in larger Haida Eddies, slightly stronger summer winds along the western Vancouver Island shelf do not result in appreciable changes to either the cross-shelf upwelling or to the magnitude of Juan de Fuca Eddies or the timing of their formation. However, increased flows are projected in some seasons for the Rose Spit, Middle Bank, and Goose Island Bank eddies. More precipitation over the watersheds emptying into coastal waters produces larger freshwater discharges and, in particular, a stronger estuarine flow in Juan de Fuca Strait and a stronger Vancouver Island Coastal Current. Generally increasing winds and decreasing density mean that the winter minus summer range of sea surface heights is projected to increase all along the coast.  相似文献   

Accelerating the sustainability transition: Exploring synergies between adaptation and mitigation in British Columbian communities     

《Global Environmental Change》2014

While the focus of government climate change policy in many regions is on mitigation, research shows that integrated approaches, focusing equally on mitigation and adaptation, seen in the context of more general sustainability goals, may ultimately yield more productive outcomes. Since 2008, the province of British Columbia has mandated that local governments be carbon neutral in their own operations and has used a suite of policies, outreach and incentive tools to enable them to do so. The Meeting the Climate Change Challenge project explored eleven leading communities in B.C. to empirically examine how climate change policies and innovations are being framed and considered at the local scale.In this paper, we examine the synergies and trade-offs between adaptation, mitigation, and sustainability. Our findings suggest that, among leading communities, pursuing an integrated sustainability strategy (rather than a narrow focus on climate change) has the potential to yield benefits for both adaptation and mitigation in the majority of cases. The findings suggest that communities leading on climate innovation in the province have moved beyond a siloed approach in considering mitigation and adaptation. These findings have implications on integrated decision making at the municipal scale and multi-level governance, identifying both the challenges and the benefits inherent in pursuing multiple priorities simultaneously.  相似文献