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181.
The huge, up to 40-50 cm long bivalves, Lithiotis, Cochlearites and Lithioperna, which dominated within “Lithiotis” facies (sensu – Fraser et al., 2004 with lit-erature cited therein), are most significant representa-tives of buildup-maker of shallow marine/lagoonal bivalve mounds (reefs) in numerous places of Tethyan- Panthalassa margins during Pliensbachian-Early Toar-cian times. The distribution of Lithiotis-facies bivalves from Western (Spain, Italy) and Middle Europe (Slo-venia, Croatia, Albania) trough north Africa (Morocco) and Arabian Peninsula (Oman, Arabian Emirates) up to Timor Island, Himalaya Mts (Nepal, China) and west-ern margin of both Americas (USA, Peru) indicates world-wide, rapid expansion of such Lithiotis-type bivalves (Leinfelder et al., 2002; Fraser et al., 2004; Krobicki et al., 2008). The Early Jurassic migration routes were connected both with break-up of Pangea and oceanic circulation, which facilitated high speed of distribution of larva’s of such oyster-like bivalves.  相似文献   
182.
根据新疆塔城盆地4个气象站1961—2009年实测资料,统计分析了塔城盆地49 a气温、降水的变化特征,结果显示:近49 a塔城盆地年、季平均气温呈显著增暖的趋势,尤其以秋、冬两季的增暖更为显著,对年际增暖的贡献较大。气温偏暖年多发生在20世纪80年代以后,气温偏冷年多发生在20世纪60、70年代。塔城盆地年降水量亦呈上升趋势,年降水最多年多出现在气温相对偏暖的20世纪90年代,而降水最少年多出现在气温偏低的60年代。降水量的显著性检验显示,四季中除冬季外均通过了0.01的显著性水平检验,表明春、夏、秋三季对塔城盆地年降水量增多都有贡献。  相似文献   
183.
无人机遥感在三维地形建模中的应用初探   总被引:2,自引:1,他引:1  
针对现有3D GIS建模中使用卫星及载人航空遥感资料中存在实时性、经济性等较差的问题,提出了引用无人机遥感影像资料进行三维地形建模的方法,并以土地利用为例进行三维地形建模,实验表明使用无人机遥感影像图片进行三维地形建模,具有更清晰、逼真的虚拟现实效果。  相似文献   
184.
正The Eglab-Yetti region of southwestern Algeria is a main part of the Reguibat shield of the West African craton(WAC)which consists of Archean to Paleoprotzrozoic basement.The region hosts numerous  相似文献   
185.
186.
硅质海绵动物是地球上最简单、最古老的多细胞动物,它经几百万年的自然进化成就了适应自然和接近完美的技术蓝图,为人类利用纳米生物技术仿生合成生物无机矿物材料提供了一种崭新的节能和"环境友好"技术,在光纤、微电子和生物医学材料等领域具有广阔的仿生应用前景.生长在深海1000 m以下水深的单根海绵动物的根须骨针长达3 m,是世...  相似文献   
187.
60年代,闽中首次发现金矿点,几经查勘,至今尚未取得突破。笔者从控矿构造,矿源、热源、成矿物理化学条件,探异常、遥感地质信息等方面进行分析,认为以英安斑岩及其隐爆角砾岩为主的次火岩对本区金矿形成起决定性作用,应以次火山岩型-斑岩型金矿为找矿重点。  相似文献   
188.
Sediments of the western part of the Valjevo-Mionica basin (Serbia) were examined both geochemically and mineralogically to explain, on the basis of their sedimentologicai characteristics, the causes of changes in their qualitative and quantitative composition. A total of 62 samples obtained from the drillhole at depths up to 400 m was investigated. Using correlation of the obtained data, six geochemical zones were defined, two of which being specially distinguished by their mineralogical, geochemical and sedimentological characteristics. The first one, upper zone A, consists of banded marlstones interbedded with clay and oil shales and is characterized by presence of analcite and searlesite. These minerals and very high contents of Na20 indicate sedimentation in alkaline conditions with increased salinity in arid climate. That provided pronounced water stratification, as well as higher bioproductivity in the basin and sedimentary organic matter preservation. Therefore, the zone A sediments are characterized by high organic matter contents of the type which provides good potential for production of liquid hydrocarbons. Another specific zone, zone F, contains sediments with very high MgO, K2O and Li concentrations. Their geochemical correlation, as well as almost complete absence of illite in this zone, indicates the presence of interstratified clay mineral type illite-saponite (lithium-bearing Mg-smectite).  相似文献   
189.
Weather manifests in spatiotemporally coherent structures. Weather forecasts hence are affected by both positional and structural or amplitude errors. This has been long recognized by practicing forecasters(cf., e.g.,Tropical Cyclone track and intensity errors). Despite the emergence in recent decades of various objective methods for the diagnosis of positional forecast errors, most routine verification or statistical post-processing methods implicitly assume that forecasts have no positional error.The Forecast Error Decomposition(FED) method proposed in this study uses the Field Alignment technique which aligns a gridded forecast with its verifying analysis field. The total error is then partitioned into three orthogonal components:(a) large scale positional,(b) large scale structural, and(c) small scale error variance.The use of FED is demonstrated over a month-long MSLP data set. As expected, positional errors are often characterized by dipole patterns related to the displacement of features, while structural errors appear with single extrema, indicative of magnitude problems. The most important result of this study is that over the test period, more than 50% of the total mean sea level pressure forecast error variance is associated with large scale positional error. The importance of positional error in forecasts of other variables and over different time periods remain to be explored.  相似文献   
190.
In multi-functional mountainous landscapes worldwide, conservation of natural values is a major task. Here, pro-active policies can be a way forward. National Environmental Quality Objectives(EQO) to solve environmental problems for future generations, however, often wrestle with being too visionary and lacking specificity, which complicates their implementation. The EQO "A Magnificent Mountain Landscape" that has been adopted by the Swedish Parliament in 1999 to preserve the pristine mountain environment in Sweden, experiences all these flaws. To aid its implementation, we studied the conditions and processes needed to define, to evaluate, and to preserve its goals across the Swedish mountain chain, using one of its milestone targets(a landscape characterized by grazing) as a study system. Applying qualitative and quantitative methods, we analyzed three types of data: 1) referral responses to the governmental strategy document, 2) interviews with relevant actors, and 3) environmental monitoring data(reindeer position data). Nationally,our results suggest a need for geographical differentiation to match regional/local conditions. Regionally, difference in both perception and definition of the milestone target among the actors hinders the formulation, monitoring, and evaluation of a common goal. Next to a culture-nature divide, we found that a "within as a user" and "from the outside as an observer" perspective influenced suggested definitions. Moreover, we found a need for better defining whether the goal is maintaining current conditions or restoring previous ones. Our result supports the use of animal position data as a decision support tool to monitor and to aid evaluation of the target. Given the number of actors involved and conflicts of interests present, we suggest the application of a structured decision process to accomplish agreements on a common goal. Here, environmental monitoring data can aid a "landscape assessment step" as a natural part in the decision process to target landscape management actions resourcefully and effectively.  相似文献   
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