李梅锌矿床地质特征及其成因   总被引：15，自引：0，他引：15  

夏新阶  舒见闻 《大地构造与成矿学》1995,19(3):197-204

李梅锌矿床是渔塘超大型铅锌矿床的重要组成部分，是近年运用地洼学说预测，经初步验证查明的大型矿床。主要组分锌＞５％，铅很低。矿体主要赋存于下寒武统清虚洞组台地边缘藻礁灰岩相中，为同生构造组合、穹窿、北北东和北西西向地洼构造所控。属多因复成矿床，地台阶段主要是矿源层经压溶作用形成构造压溶热液成矿，在地洼阶段可能是渗流热液成矿，铅锌等成矿物质来自寒武纪碳酸盐围岩，主要成于低温。  相似文献   

四川某磷矿床地质特征     

段前烈  沈志高  舒鑾綬  章炎生 《中国地质》1964,(4)

这个磷矿是在一九五八年到六○年发現的磷块岩矿床。形成时代为晚泥盆世。这种上泥盆統地层中的具有工业价值的磷矿床,在我国和世界上都很少見。这种矿床規模大、品位富,在矿石物质成分、矿石类型等方面也都独具一格,并且首次在沉积矿床中  相似文献   

扬子地台西缘钾质煌斑岩类的岩石学研究   总被引：3，自引：0，他引：3  

舒小辛 《岩石学报》1994,10(3):248-260

扬子地台西缘钾质煌麻岩的矿物组合中缺少钾碱镁门石、柱红石等富钾贫铝矿物，其辉石和白榴石富Ａｌ２Ｏ３，金云母贫ＴｉＯ２，透长石的Ｎａ２Ｏ含量高。全岩Ａｌ２Ｏ３高，Ｋ２Ｏ／Ａｌ２Ｏ３（＜０．７）低，（Ｇｄ／Ｙｂ）Ｎ低。岩体中含有二辉橄榄岩包体、镁铝榴石捕虏体晶。这些特点表明其岩浆源区的亏损程度低。此外，钾质煌斑岩明显亏损Ｎｂ、Ｔｉ，可能是与其源区经受过板块边缘活动影响有关。  相似文献   

城市物探—综述     

亨德.  RJ  吴其斌 《国土资源信息化》1994,(5):38-42

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DB—3滚筒停转报警器     

舒优良 《地震地磁观测与研究》1994,15(1):76-78

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Investigation of recreational boats as a source of copper at anchorage sites using time-integrated diffusive gradients in thin film and sediment measurements   总被引：1，自引：0，他引：1  

Warnken J  Dunn RJ  Teasdale PR 《Marine pollution bulletin》2004,49(9-10):833-843

Antifouling paints on small to medium recreational vessels were first recognized as an important source of pollution in the 1970s. One of the principle biocides in these paints is Cu. Results from a field program in the Gold Coast Broadwater, Queensland, demonstrate a clear correlation between recreational boat numbers at anchorage sites and water column Cu concentrations, for both time-integrated 24 h DGT measurements (n=14, r=0.815, p<0.001) and measurements on composite 0.45 mum-filtered grab samples (n=14, r=0.698, p<0.01) collected every 4 h over 24 h. At boat numbers above 30 the 0.45 microm-filterable Cu concentrations were mostly above the relevant guideline value (1.3 microgl(-1)) but the DGT-reactive Cu concentrations were well below this value at all boat numbers studied. For three-day DGT deployments in Moreton Bay, Queensland, correlations between Cu levels and vessel numbers were not observed, possibly because of uncertain estimates of boat numbers. However, using a multi-factorial ANOVA, DGT-reactive Cu concentrations showed a significant effect for 'sites with vessels vs. sites without vessels' (alpha=0.10, p=0.077) and for 'sampling period' (non-holiday weekdays, weekends, holiday weekdays, holiday weekends) at alpha=0.10, p=0.02. Cu levels in sediments at the same sites were strongly influenced by fraction of clay (<63 microm) material but also by whether the samples were collected at an anchorage or control site. Results from this study further support the view that Cu emissions from antifouling paints may become an important source in waters with high boat numbers and should be taken into account when designing management instruments for coastal waterways.  相似文献   

Stepwise use of GFLOW and MODFLOW to determine relative importance of shallow and deep receptors   总被引：1，自引：0，他引：1  

Feinstein D  Dunning C  Hunt RJ  Krohelski J 《Ground water》2003,41(2):190-199

A stepwise modeling approach is implemented in which a regional one-layer analytic element model is used to simulate the flow system and to furnish boundary conditions for an extracted local three-dimensional model. In this case study the stepwise approach is used to evaluate the fate of recharge in the Menomonee Valley adjacent to Lake Michigan. Two major receptors exist for recharge that flows through contaminated valley fill: the surface water estuary and a tunnel system constructed approximately 75 to 110 m below land surface to store storm runoff. The primary objective of the modeling is to delineate the contributing areas of recharge to each receptor. Of interest is the ability of the one-layer regional model to furnish flux boundary conditions to the local three-dimensional model despite the presence of vertical flow conditions at the boundaries of the local model. Sensitivity analysis suggests that the local model was insensitive to the vertical distribution of the flux. Each step of the modeling approach demonstrates that both receptors play an important role in capturing valley recharge. The pattern of capture of the one-layer model differed in shape from that delineated by the multi-layer local model in the presence of a flow system with pronounced vertical anisotropy and with sinks drawing water from different elevations.  相似文献   

Simulating ground water-lake interactions: approaches and insights   总被引：4，自引：0，他引：4  

Hunt RJ  Haitjema HM  Krohelski JT  Feinstein DT 《Ground water》2003,41(2):227-237

Approaches for modeling lake-ground water interactions have evolved significantly from early simulations that used fixed lake stages specified as constant head to sophisticated LAK packages for MODFLOW. Although model input can be complex, the LAK package capabilities and output are superior to methods that rely on a fixed lake stage and compare well to other simple methods where lake stage can be calculated. Regardless of the approach, guidelines presented here for model grid size, location of three-dimensional flow, and extent of vertical capture can facilitate the construction of appropriately detailed models that simulate important lake-ground water interactions without adding unnecessary complexity. In addition to MODFLOW approaches, lake simulation has been formulated in terms of analytic elements. The analytic element lake package had acceptable agreement with a published LAKI problem, even though there were differences in the total lake conductance and number of layers used in the two models. The grid size used in the original LAKI problem, however, violated a grid size guideline presented in this paper. Grid sensitivity analyses demonstrated that an appreciable discrepancy in the distribution of stream and lake flux was related to the large grid size used in the original LAKI problem. This artifact is expected regardless of MODFLOW LAK package used. When the grid size was reduced, a finite-difference formulation approached the analytic element results. These insights and guidelines can help ensure that the proper lake simulation tool is being selected and applied.  相似文献   

The loss of the chemical tanker Ievoli Sun in the English Channel,October 2000     

Law RJ  Kelly C  Matthiessen P  Aldridge J 《Marine pollution bulletin》2003,46(2):254-257

A chemical product tanker, The Ievoli Sun, was abandoned and later sank approximately 11 miles NW of Alderney in the English Channel in October 2000. The vessel carried a mixed cargo comprising 4000 tonnes of styrene, and 1000 tonnes each of methyl ethyl ketone and isopropyl alcohol. These chemicals are of low to moderate toxicity to aquatic life, are not persistent and have a low potential for bio-accumulation. Both of the solvents are miscible in water, whilst styrene is practically insoluble and, following release, it will rise to the sea surface and rapidly evaporate. More than 1000 tonnes of styrene are believed to have been lost to sea during the incident, resulting in an aerial plume of vapour which crossed Alderney and episodic contamination of air and water in the immediate vicinity of the wreck site. Analysis of edible tissues using coupled gas chromatography/mass spectrometry demonstrated low-level styrene contamination of crabs recovered from pots laid very close to the wreck site prior to the incident. These concentrations posed no risks to human consumers, and no fishery controls were implemented. The remainder of the styrene and the ship's main bunker fuel were recovered from the wreck on the seabed, whilst the two chemical solvents were released to the water column in a slow, controlled manner.  相似文献   

基于GPS和GSM的公安专用跟踪系统     

舒金表  皮亦鸣 《全球定位系统》2004,29(4):29-33

采用GPS定位与GSM网络场强定位技术相结合实现了一款公安专用跟踪系统。该系统比一些常规的跟踪系统更加具有精确性、实时性和不间断性。系统的跟踪终端主要包含了GPS模块、GSM功能单元和MCU控制电路三大部分。  相似文献