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261.
<正>Three major threats to ocean security and coastal zone sustainability - global warming,the loss of ocean biodiversity,and pollution - are combining to threaten the ecological integrity of our marine environment and life support systems.We put forward a geomatics-based systems engineering architecture to identify the location and extent of oil spills,thereby improving the ecological integrity of the world's oceans and helping contingency planners to determine required assets,personnel and other resources.This real-time,event-based and cost effective emergency management decision support system can aid in the classification,detection,and monitoring of oil spills in the marine environment.The developed Synthetic-Aperture Radar(SAR) processing and calibration techniques efficiently monitor environmental changes in inaccessible ocean regions,characterize oil spill scenarios,and help to identify spill sources.The system is used to improve emergency management in the Gulf of Mexico,with application to oil spills arising from Hurricane Katrina.  相似文献   
262.
关于科学的几个问题   总被引:2,自引:0,他引:2  
本文认为,科学与哲学和文化是紧密联系的,不可分割的,因此科学也是多元的,由于中西方文化有巨大差异,因此,中西方科学也有本质不同。  相似文献   
263.
论大宝山矿床成因   总被引:1,自引:0,他引:1  
通过对大宝山矿区各矿床产出的地质环境,矿体产状,矿石类型和结构构造,矿石稳定同位素特征,稀土元素特征,成矿温度等方面的研究,论证矿区的成矿历史分2个成矿期,4个成矿介段,即中泥盆世多金星成矿期的铜铜锌银硫化物成矿阶段,菱铁矿成矿阶段;早白垩世铁钼钨成矿期的铁钨成矿阶段,钼钨成矿阶段,各阶段均有各自的成矿地质环境和成矿方式,构成一个在空间上关系密切,成历上有一定联系,时间上差别明显的矿床系列。  相似文献   
264.
哀牢山和右江西部是华南板块古大陆边缘海西—印支期火山活动最频繁的地区之一。文章通过对该区火山岩的岩石学和地球化学综合分析,认为火山岩产于洋盆裂谷系、被动大陆边缘裂谷系、不成熟岛弧和弧后盆地裂谷系四种不同的板块构造环境中。有意义的是古特提斯洋板块相对华南板块于海西期扩张和印支期俯冲,哀牢山和右江西部的火山岩和板块构造环境出现相对应的同步演化关系。  相似文献   
265.
Contents of Fe, Mn and other elements in four ferromanganese crusts recovered from the central North Pacific are analyzed at high depth-resolution by electron microprobe for reconstructing factors controlling their deposition. Manganese (IV) in hydrogenetic ferromanganese crusts is mainly supplied as colloidal precipitates from the Oxygen Minimum Zone (OMZ), which concentrates high amounts of dissolved Mn (II). The iron is derived from carbonate dissolution and silicate particles of eolian dust. An increase in paleoproductivity during cooler climate would potentially lead to a decrease in Mn deposition due to enlargement of the OMZ which has a “temporary storage” effect for Mn. On the other hand, not affected by the OMZ, the iron entering the Fe-Mn crust would likely increase with the eolian dust input and surface productivity at glacial stages. As a result, the increasing FeMn ratio should indicate a cooling climate. This is supported by the following observations. In the profile of the past 1 Ma, the variations of FeMn ratio coincide with benthic oxygen isotope fluctuation in glacial-interglacial cycles. Three episodes with high FeMn ratios, approximately at 2.6, 1.8 and 0.8 Ma, are detected within the past 3 Ma and coincide with major climate transitions and cooling events. The secular evolution pattern of FeMn ratio in the Cenozoic is similar to the Pb isotope evolution which is mainly controlled by eolian dust and related to climate. The FeMn evolution pattern is also broadly consistent with the global deep-sea oxygen isotope records. Therefore, FeMn ratio recorded in the ferromanganese crusts may be a new proxy for climate change.  相似文献   
266.
西部地区旅游资源经济评价   总被引:2,自引:0,他引:2  
从旅游业的竞争优势、资源评价、组合条件、定位优势和调整方向等方面分析了中国西部旅游业的发展现状,从交通、资金、基础设施、经营管理、地域观念等方面分析了西部旅游业的制约因素,研究了西部旅游业开发的指导中心、观念和原则,指出了西部旅游业在市场促销、形象定位、节事营销、生态发展、绿色体系、精品示范、电子网络、脱贫致富和教育服务等方面的开发战略.  相似文献   
267.
Cobalt-rich ferromanganese crusts occur throughout the global ocean on seamounts, ridges, and plateaus where currents have kept the rocks swept clean of sediments for millions of years. Crusts are important as a potential re-source for primarily cobalt, but also for titanium, nickel, REE, PGE, and other elements. Most Co-rich crusts pre-cipitate at water depths of about 1000-3000 m, and are easy to be exploited. Besides the high cobalt contents compared to abyssal Fe-Mn nodules, exploitati…  相似文献   
268.
The genesis of the Carboniferous volcanic rocks in the Dahalajunshan group, mainly consisting of trachytes and trachy-andesites and distributing widely in western Tianshan Mountains, remains to be controversial. It has been proposed to be relevant to “rift” or “plume”. Detailed petrology and geochemical data presented in this paper show that these volcanic rocks represent typical continental arc magmatism. The volcanic rocks are mainly trachy-andesitic, and the magma source is enriched in LILE, Th and Pb, and depleted in HFSE and Ce. Trace element geochemical study suggests that the basalts could be modeled by 7% -11% partial melt of garnet Iherzolite. The volcanic rocks in the Dahalajunshan group are neither the products of “rift” nor so-called “plume”but represent the continental island arc of the Paleo-Southern Tianshan Ocean. The mantle wedge had been modified by the melt generating in subduction zone during a long evolution history of this island arc. The continental crust materials (i.e. mainly sediment on ocean floor) had been added into island arc through melt in subduction zone. Volcanic rocks occurring in different regions might represent magma eruption in different time. The zircon SHRIMP dating indicates that the ages of the basalt varies between 334.0 Ma and 394.9 Ma. The 13 analyses give an average age of 353.7±4.5 Ma (MSWD = 1.7). The apparent ages of zircons in trachy-andesite vary between 293.0 Ma and 465.4 Ma. All analyses fall on the U-Pb concordant line and are divided into two groups. 8 analyses produce an average age of 312.8±4.2 Ma (MSWD = 1.7), which represents the crystallizing age of zircon rims in trachy-andesite. The acquired two ages (i.e. 354 and 313 Ma) belong to the Early Carboniferous and Late Carboniferous epochs, respectively. Thus, the Dahalajunshan group would be separated into several groups with the accumulation of high-quality age dating and data of trace element and isotopic geochemistry, in our opinion.  相似文献   
269.
提出了基于声多普勒渡流混合测量方法,建立了相应测量方法的数学模型,并为提高波浪方向谱的反演精度设计了新型的测渡阵。利用模块化,工业化的思想设计出系统实现方案,为发射机设计了非相关和相关混合的发射测量波形,使之在较大的测量范围内能提高测量的空间分辨率。  相似文献   
270.
目的:中西医结合治疗隆起型和破裂游离型腰椎间盘突出症的疗效观察;方法予以脱水、电动牵引、手法推拿按摩、内服中药、腰椎硬脊膜外腔注射等综合治疗。结果隆起型:有效率90.24%,治愈率75.60%;破裂游离型:有效率68.42%,治愈率42.10%。结论中西医结合治疗隆起型腰椎间盘突出症疗效明显优于破裂游离型。  相似文献   
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