新疆东准噶尔蚀变矿物填图及多元信息找矿   总被引：9，自引：0，他引：9  

周军  陈明勇  高鹏  刘磊  李得成  田勤虎 《国土资源遥感》2005,(4):51-55,i0003

选择Crosta和主成分分析方法对新疆青河、奇台、巴里坤一带进行矿化蚀变信息提取，以μ＋1．64σ～μ＋2σ、p＋2σ～p＋3σ及〉μ＋3σ三级阈值分割遥感异常信息，并按不同色彩叠加于1：20万或1：5万化探数据与遥感数据融合的图像上，经综合分析和部分实地查证，提出青河小萨尔布拉克、科克玉依、喀拉套弧形构造、奇台北塔山牧场场部、乌伦布拉格以及巴里坤大红山及草湖沟等为重要找矿地段。  相似文献   

左江洪涝特征分析   总被引：1，自引：0，他引：1  

张健 《气象研究与应用》2005,26(3):24-26

台风是造成左江洪涝的主要影响系统,后汛期洪涝频率明显高于前汛期,洪水汇流量与降雨性质、地形地貌、土壤含水量有关,依不同降雨量径流量不同的原理及洪涝特征估测洪水量、洪峰流量较接近实况,具有应用价值。  相似文献   

Consolidation and Break-up of the South American Platform in Southeastern Brazil: Tectonothermal and Denudation Histories   总被引：1，自引：0，他引：1  

P.C. Hackspacher  L.F.B. Ribeiro  M.C.S. Ribeiro  A.H. Fetter  J.C. Hadler Neto  C.E.S. Tello  E.L. Dantas 《Gondwana Research》2004,7(1):91-101

The different tectonic stages that occurred at the end of the Proterozoic and during the Phanerozoic have an important bearing on the tectonothermal history of the South American Platform and its consolidation. Geochronological data (U/Pb monazite, ⁴⁰Ar/³⁹Ar whole rock) and apatite fission-track analysis, from Precambrian rocks of the southeastern Brazilian coastline, permit the modeling of a long-term thermal history of the crust and constrain variable denudation rates.Using these data, a temperature-time diagram reflects a period of accelerated exhumation during the end of the Brasiliano Orogeny, followed by long stability and reactivation of the platform during the Rifting Phase of the South Atlantic Ocean.U/Pb zircon and monazite (blocking temperature of ca. 650° C) data from a series of igneous bodies suggest that a tangential and transpressional tectonic regime occurred between 625 and 610 Ma. During the following escape tectonics, between 610 and 590 Ma the exhumation process indicates cooling rates of ca. 12°C/Ma. ⁴⁰Ar/³⁹Ar biotite ages between 540 and 510 Ma (ca. 300°C) and a corrected fission-track age on apatites (100°C) of 480 Ma indicate an exhumation event related to block tectonics with huge vertical displacement along shear zones.A long stabilization phase, with low exhumation, and cooling rate around 0.25°C/Ma was recorded from the Cambro/Ordovician to the Mesozoic. At 65 Ma an acceleration of the exhumation through denudation and reworking of the South American surface with cooling rate of 1.5°C/Ma is observed.The uplift of the Mantiqueira and Serra do Mar mountain ranges along the southeast Brazilian coastline works as a climatic barrier provoking lateral erosional processes causing long-term scarp retreat, combined with intense, but progressive denudation towards the continent. A denudation of 2.5 to 4 km was calculated for such processes. This lateral retreat of escarpments and flexural response can provide important insights regarding marginal isostatic uplift and the evolution of offshore sedimentary basins of southeast Brazil.  相似文献   

Optimisation of the Operation of an Electrochemical Process To Treat TBT‐contaminated Sediments on a Pilot Scale     

Eduardo Arevalo  Arne Keller  Heinz Stichnothe  Wolfgang Calmano 《洁净——土壤、空气、水》2004,32(6):401-410

Since at least three decades tributyltin had been commonly used in paint formulations to protect ship hulls and submersed surfaces from fouling. This has resulted in negative and Technology, effects to the marine environment due to its high toxicity towards non‐target organisms and to its accumulation in sediments, especially near point sources of pollution. Even if a ban of TBT for its application in anti‐fouling paints is enforced the problem of TBT‐contaminated sediments will remain for the coming years due to the low degradation rates of organotin in sediments. In this work an electrochemical process at a pilot scale to destroy TBT in sediments was investigated. Previous experiences at a laboratory and technical scale have demonstrated the potential of this process to electrolytically degrade organotin species in sediments. This article deals with the optimisation of the pilot plant performance in terms of organotin degradation and operation costs monitoring additionally the effect of the electrochemical treatment on other pollutants such as heavy metals, PCBs, and PAHs. The aim was to investigate by means of a parametric study the range of operating conditions required to destroy TBT down to concentrations lower than 100 μg/kg; to determine the influence of those parameters on the performance of the process; and to evaluate the operation costs associated to the process. It was determined that it was possible to destroy TBT down to 100 μg/kg at current densities in the range of 4.4 to 6.6 mA/cm² and chloride concentrations of least of 0.2 mol/L with operation costs of 13 to 18 EUR/m³.  相似文献   

2002年12月17日玉门M_L4.5地震的强震仪多条记录资料分析          下载免费PDF全文

何少林  闵祥仪  何新社 《地震工程学报》2004,26(3):274-279

对2002年12月17日玉门ML4．5地震近场多道强震仪的加速度记录进行了分析处理，校正了仪器响应和基线，计算了速度和位移时程曲线及各种谱值，并对记录特点做了分析。  相似文献   

喀什地磁台数字与模拟记录K指数对比分析   总被引：1，自引：0，他引：1  

孙海军  高守全 《内陆地震》2007,21(4):348-353

介绍了喀什地磁台地磁数字记录K指数的计算机FM I测定方法和传统的模拟测定K指数方法,分析比较了数字和模拟测定K指数存在的差异和原因。与国家地磁台网2005年统计的平均数据进行了比较,数字记录测定比模拟测定的值更好,数字记录更真实、更准确地反映出地磁场活动状态,因此在实际量算K指数时应以数字测定为准。  相似文献   

库仑法测定煤中全硫必须重视的问题     

雷翠琼 《云南地质》2007,26(4):458-460

煤中全硫测定是煤质分析的一项重要指标。本文从煤样的粒度和均匀性,载气流量,电解液的使用,电解池和电极片的处理,库仑测硫仪的校正等方面对应用库仑法测定煤中全硫应注意的问题及原因进行分析,以确保测定结果的准确性。  相似文献   

The mechanics of mudslides as a cyclic undrained–drained process     

Luca Comegna  Luciano Picarelli  Gianfranco Urciuoli 《Landslides》2007,4(3):217-232

Data collected by monitoring suggest that the movement of mudslides essentially develops through alternating stages of undrained–drained deformation. Undrained conditions are established as a consequence of landslide mobilisation or reactivation. Every acceleration phase is followed by progressive deceleration associated with dissipation of excess pore pressure. This paper reports the results of some simple numerical analyses performed to investigate the role of pore pressure on mudslide behaviour.  相似文献   

Error inflation in Probabilistic Seismic Hazard Analysis     

Jens-Uwe Klügel   《Engineering Geology》2007,90(3-4):186-192

Based on a consistent interpretation of earthquake occurrence as a stochastic process I demonstrate that the mathematical model of Probabilistic Seismic Hazard Analysis (PSHA) as it is in use today is inaccurate and leads to systematic errors in the calculation process. These mathematical errors may be regarded as an important contributor to the unrealistic results obtained by traditional PSHA for low probabilities of exceedance in recent projects.  相似文献   

连云港市城市空气质量预报方法研究   总被引：6，自引：0，他引：6       下载免费PDF全文

姜有山  陈飞  班欣  李军 《气象科学》2007,27(2):220-225

本文利用高空大气探测资料和有限区细网格模式的数值预报产品,分别建立统计预报和数值预报等适合连云港市城市空气质量预报业务发展所需要的客观预报方法,最终利用动态分权法,综合决策集成连云港市城市空气质量预报。结果表明:动态分权法能够有效地提高空气质量的预报准确率。  相似文献