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991.
Thematic maps can be analyzed by multiple regression for (1) forward prediction where a younger geological structural map is written as a least-squares function of older maps for information on historical perspectives or (2) by backward prediction where an older map is regressed stepwise on a series of younger ones to aid in prospecting. The technique was evaluated by a series of structure maps on different geological horizons from the U.S. Midcontinent (Kansas) where the forward prediction proved more effective than backward. In forward prediction, the first map entered into a multiple regression is invariably the immediately underlying one as expected. On the other hand, the first map in a backward prediction is not necessarily related to stratigraphy which limits the utility of the technique for prospecting.  相似文献   
992.
This paper discusses the strategy for successfully predicting the location of potential hidden ore bodies in aged ore field,and presents the result of location prediction of hidden ore bodies in Fenghuangshan ore field,Tongling.Innovative conceptual targeting procedures based on a genetic understanding of mineralization systems,carefully geological investigation and correct deduction,together with new geochemical and geophysical technology and integrating of comprehensive information are all very important for the successful prediction.In the aged Fenghuangshan ore field,through researching by application of the metallogenic theory of polygenetic compound ore deposits and triple-frequency induced polarization method and exploration tectono-geochemical method,we predicted location and quality of hidden ore bodies.According to the prediction,hidden high quality Cu-Au ore bodies of skarn type and porphyry type have been discovered.  相似文献   
993.
Partitioning of heavy metals on soil samples from column tests   总被引:3,自引:0,他引:3  
In this study, column tests were used to determine the retention capability of three types of estuarine alluvia collected adjacent to landfill sites in South Wales. Selective sequential extraction (SSE) was used to study the retention mechanisms of heavy metals in the soil columns obtained from leaching experiments. Acid digestion was later used to check the validity of the SSE results. Breakthrough curves show good retention of heavy metal ions (Pb, Cu, and Zn) by all soils, where almost 99% of heavy metals were retained with the Ce/Co values in the order of 10−3. The retention strength of these soils was observed to be constant up to five pore volumes (PV). This corresponds with the pH of the effluents and pore water of soil slices, which also show good buffering capacity against very acidic leachate up to 5PV. The heavy metal extraction profiles from SSE show very similar trends with the retention profiles from the leaching experiments, where heavy metals were retained mainly at the top part where the leachate entered the column. SSE indicates qualitatively that heavy metals precipitated with carbonates and amorphous materials (oxides/hydroxides) are higher than heavy metal retention via exchangeable mechanisms. The mass balance calculation gives range of deviation of 1–16% of the total soil extraction. The distribution of the heavy metals with various soil constituents are ranked in the following order: Carbonates>Amorphous oxides hydroxides>Organic matter>Exchangeable phases.  相似文献   
994.
本文运用已建立的二维时变云模式[1],就中低空风垂直切变对对流和云微物理过程的影响进行了模拟研究。为此设计了五种方案进行了对比试验。结果表明:中低空风切变较小时,容易爆发对流;中低空切变不超过某一值时,对流发展缓慢,但最终会爆发强对流;一旦中低空风切变超过某一值时,则对流发展不起来。另一方面,中低空风切变可加强各云微物理过程及地面降水量。  相似文献   
995.
In this paper, a 1-D time dependent cold cumulus chemistry model is presented. In the coldcumulus model, 4 categories of hydrometeors: cloud drops, raindrops, cloud ice crystals, graupelparticles, and 18 microphysical interactions are considered, In the chemical model, the source andsink terms for pollutants include: the complicated interactions between pollutants (gases andaerosol particles) and the hydrometeors (especially ice crystals and graupel particles), the ex-changes of chemical compounds between two hydrometeors accompanying microphysical processesand the aqueous oxidations of S (IV) to S (VI). The two models are combined to study the acidifi-cation processes in cold cumulus clouds.  相似文献   
996.
In terms of observational analysis and numerical simulations,study is performed of thesynergistic effects of the tropical Indian Ocean and Pacific SSTA on the atmosphere in northern win-ter.It turns out that the SSTA features show in-phase variation for the Indian Ocean and the central/eastern Pacific at low latitudes and anti-phase change compared with that in the neighborhood of thewestern Pacific“warming pool”.When negative SSTA in the western Pacific and positive SSTA inthe central/eastern Pacific and the Indian Ocean are available,the 500 hPa height anomaly exhibits awave train of a positive-negative-positive anomaly following a great-circle path emanating from thesubtropical western Pacific via the NW portion to North America,with enhanced westerly jet overmidlatitude East Asia and the NW Pacific,and v.v.The comparison to the results from the numeri-cal modeling of the tropical western Pacific SSTA reveals the importance of the synergistic effects ofthe oceans on atmospheric circulations.  相似文献   
997.
高分辨区域输送模式中不同输送格式的对比试验   总被引:3,自引:0,他引:3  
本文对两种输送格式在理论试验的基础上,引入19层高分辨区域输送模式EM3,由中尺度模式(MM4)提供实例输送风场,积分至13、18、30、50、70小时,作分析和对比数值试验。采用的两种格式是:二阶动量矩守恒的Prather格式(以下简称为SOM)及通量订正的Smolar格式。数值试验结果表明,高精度的SOM格式使数值扩散减小一个量级, 使输送物质(SO#-[2])中心浓度比Smolar格式增大3~4倍, 采用SOM格式还明显改进了浓度中心水平平均运动轨迹的模拟精度,选择高精度的平流格式是改进模拟结果的重要途径。  相似文献   
998.
青岛地区边界层结构的数值模拟   总被引:8,自引:1,他引:8  
王卫国  蒋维楣 《大气科学》1996,20(2):229-234
本文建立了一个非静力的三维细网格边界层模式,对青岛地区复杂下垫面条件下的边界层结构和湍流特征作了数值模拟,模式采用能量闭合方案,舍弃了静力近似,以提高空间分辨率和模式精度。模拟以实测资料为初始输入,对该地区风场和湍流场作了较细致的模拟分析,与观测资料相比,结果合理地一致。结果表明了陡峭地形和不规则海岸线对局地风场和湍流场影响很大。  相似文献   
999.
区域暴雨增强数值预报业务系统及其预报效果分析   总被引:3,自引:7,他引:3  
该文介绍了区域暴雨增强数值预业务系统的设计思想,主体结构及主要的关键技术,并总结了该系统业务试验的情况和效果。该系统以YH模式为基础,对其从坐标系、水平和垂直分辨率及物理过程等方面进行了改进,并结合实时资料处理系统,图形处理等形成了一个比较完整的数值预报业务体系。  相似文献   
1000.
地震断层气监测的现状与展望   总被引:1,自引:0,他引:1  
断层气测量是地震科学研究的重要方法之一,断层气测量具有实用、轻便、快便、价廉等优点,在地震监测预报和减灾活动中具有广阔的应用前景和巨大的潜力。本文对断层气测量在地震科学中的应用和现状作了简要的介绍,同时探讨了我国地震断层气监测系统中存在的一些主要问题,对今后的发展进行了展望。最后简单介绍了几种断层气监测新技术及新型气敏传感器。  相似文献   
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