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31.
为了研究南海西南部印度尼西亚纳土纳群岛西侧西纳土纳盆地走滑构造特征及对油气的控制作用,对研究区三维地震资料进行了精细分析,并结合切片和剖面特征对走滑构造进行了刻画。研究表明盆地中部中新世晚期发育北西向右旋走滑构造,由南东向北西,构造特征存在明显差异,根据其平面、剖面特征及活动强度分为东段、中段和西段。东段平面上为平直的、贯通的主干走滑断裂和雁列断层组,剖面上为花状构造;中段平面上为S型贯通的主干走滑断裂和雁列断层组,剖面上为花状构造;而西段平面上为雁列构造,没有贯通的主干走滑断裂,剖面上主要为断阶组合。推测走滑构造的分段性受走滑强度、断层几何形态和盖层厚度的影响,并对圈闭形成和油气运移、聚集具有明显的控制作用。  相似文献   
32.
This study presents an experimental procedure to fabricate high‐purity silica glass containing a selected element at a specified mass fraction. The procedure was used to prepare glasses doped with trace‐level mass fractions of Ti with the goal of improving analytical confidence when measuring trace elements in quartz. Systematic tests were performed to determine the ideal conditions and procedures for doping nanoporous silica gel with the highest efficiency of dopant recovery. Silica gel was cleaned in concentrated HCl, immersed in a non‐polar doping medium at a controlled pH and doped with precise quantities of ICP‐MS standard solution. Using liquids composed of longer chain molecules as the doping medium diminishes recovery, suggesting that large molecules could obstruct nanopores to inhibit capillary uptake of the dopant. A control experiment using crystalline quartz reinforced the effectiveness of nanoporous silica gel for doping with trace‐level precision. Layered aggregates of silica gel doped with different Ti mass fractions were hot‐pressed to create multi‐layered reference materials that were analysed with multiple techniques at a variety of spatial scales. Analyses at the intra‐grain scale (cathodoluminescence scanning electron microscopy, electron probe microanalysis), at the single grain scale (SIMS), at the sample layer scale (EPMA, laser ablation‐ICP‐MS) and at the bulk scale (ICP‐OES) demonstrated acceptable homogeneity at sample volumes characteristic of most microanalysis techniques and show that nanoporous silica gel holds promise as a highly retentive doping substrate for preparing reference materials for laser‐, electron‐ and ion‐beam microanalysis.  相似文献   
33.
Abstract

Abstract A flood forecasting system is a crucial component in flood mitigation. For certain important large-scale reservoirs, cooperation and communication among federal, state, and local stakeholders are required when heavy flood events are encountered. The Web-based environment is emerging as a very important development and delivery platform for real-time flood forecasting systems. In this paper, the findings of a case study are presented of the development of a Web-based flood forecasting system for reservoirs using Java 2 platform Enterprise Edition (J2EE). J2EE of Sun Microsystems is chosen as the development solution for the Web-based flood forecasting system, Weblogic 6.0 of BEA as the container provider, and JBuilder 7.0 of Borland as the development tool. One of the key objectives in this project is to establish a collaborative platform for flood forecasting via Web technology in order to render hydrological models and data available to stakeholders and experts involved and thus offer an efficient medium for transferring and sharing information, knowledge and experiences among them. Compared with general Web-based query systems and traditional flood forecasting systems, the Web-based flood forecasting system is more focused on the on-line analysis of model-based forecasting of floods and provides opportunities for improving the transfer of information and knowledge from the hydrological scientists and managers to decision makers. Finally, a prototype system is used to demonstrate the system application.  相似文献   
34.
Abstract

Abstract The utility of simulations of Global Climate Models (GCMs) for regional water resources prediction and management on the Korean Peninsula was assessed by a probabilistic measure. Global Climate Model simulations of an indicator variable (e.g. surface precipitation or temperature) were used for discriminating high vs low regional observations of a target variable (e.g. watershed precipitation or reservoir inflow). The formulation uses the significance probability of the Kolmogorov-Smirnov test for detecting differences between two distributions. High resolution Atmospheric Model Intercomparison Project-II (AMIP-II) type GCM simulations performed by the European Centre for Medium-Range Weather Forecasts (ECMWF) and AMIP-I type GCM simulations performed by the Korean Meteorological Research Institute (METRI) were used to obtain information for the indicator variables. Observed mean areal precipitation and temperature, and watershed-outlet discharge values for seven major river basins in Korea were used as the target variables. The results suggest that the use of the climate model nodal output from both climate models in the vicinity of the target basin with monthly resolution will be beneficial for water resources planning and management analysis that depends on watershed mean areal precipitation and temperature, and outlet discharge.  相似文献   
35.
Bog systems tend to have a flashy hydrological regime with low baseflows and rapid and high storm peaks. Water derived from peatlands often contains significant amounts of organic humic and fulvic materials which form the largest fraction of the dissolved organic carbon component of the fluvial carbon flux. However, most estimates of dissolved organic carbon flux from peatlands are based on sampling that is infrequent and which may miss the periods of high flux during storm events. In order to better characterize the behaviour and fluxes of fluvial carbon it is necessary to operate more frequent sampling. This paper presents data from a continuously operating field‐based spectrophotometer simultaneously measuring absorbance across 200–730 nm at 2·5 nm intervals in runoff from an upland peatland stream. It is shown that absorbance at different wavelengths that have previously been used to characterize dissolved organic carbon varies rapidly during storm events. The probe is shown to even detect changes in absorbance characteristics in response to rainfall events before the stream discharge starts to rise. The high‐resolution behaviour of absorbance characteristics during storm events is different depending on the wavelength studied. Thus, the choice of wavelength used as a proxy for dissolved organic carbon needs careful attention and it may be that automated spectrophotometric methods which provide rich time‐series data from across the spectrum can tell us more about fluxes, processes and sources of aquatic carbon in peatland systems in the future than traditional practices have hitherto allowed. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
36.
雁列式断层变形过程中物理场演化的实验研究(一)   总被引:21,自引:3,他引:21  
马胜利  邓志辉 《地震地质》1995,17(4):327-335
在双轴压缩条件下对挤压型和拉张型雁列式断层变形破坏过程中声发射、断层位移及应变场的时空演化进行了实验研究。研究表明,两类雁列式断层具有类似的变形破坏过程,即前期以雁列区的破裂贯通为主,后期以沿断层的滑动为主。但挤压型雁列区内可积累较高的应变能,有较强的应变释放和声发射活动,雁列区对滑动始终起着阻碍作用;而拉张型雁列区内难以产生快速的应变释放和较强的声发射活动,雁列区对后期的滑动也无明显的阻碍作用。两类雁列区贯通所引起的失稳均有明显的前兆,而在随后滑动过程中失稳前兆的出现,取决于断层不同部位或段落之间是否有应变传递  相似文献   
37.
雁列式断层变形过程中物理场演化的实验研究(二)   总被引:6,自引:1,他引:6  
马胜利  刘力强 《地震地质》1995,17(4):336-343
在双轴压缩条件下对由挤压型和拉张型雁列式断层组合而成的复杂雁列断层系变形过程中声发射、断层位移及应变的时空演化进行了实验研究,结果表明,复杂雁列式断层系的变形过程及相应的物理场演化并非是两种雁列式断层的简单叠加,而是包含着它们之间的相互作用。能量较强的声发射事件成核部位主要集中在应力水平较低的张性雁列区附近的主于断层上,而不是应力水平较高的压性雁列区,但这种事件发生的时间则明显受控于压性雁列区的变形过程  相似文献   
38.
鲜水河断裂与则木河断裂在几何学特征、运动学特征和地震活动性方面既有明显的相似之处,又有着重要的差别。由于这两条断裂带都位于川滇菱形块体的北东边界,同属川西巨型左旋走滑断裂带的组成部分,因此在断裂的几何格局、活动方式和地震活动等方面有许多相似之处。然而,在菱形块体自北西向南东方向运动的过程中,由于其东部受到四川地块的阻挡使得块体边界的位移呈现由北西向南东递减的趋势,进而造成了两条断裂带在地震活动性方面的差异。根据详细的野外调查和已有成果,我们认为,断层的活动方式、滑动速率以及变形和变位的调整方式等运动学特征决定了两条断裂带在地震活动性方面的特征,而这些又与断裂带的几何学特征及与周围断裂的组合方式密切相关。通过对两条断裂带的对比研究,可以使我们对每条断裂有更好的理解和深入的认识。  相似文献   
39.
The low recharge of reservoirs and the increasing demand for water limit the potential of mobilized resources, especially in arid to semi-arid areas like Morocco. Integrated management is essential to safeguard this resource. In respect with this perspective, this work provides the analysis of hydrogeological potential of Khemisset-Tiflet region, which falls within the action area of the Sebou Hydraulic Basin Agency. The basis of our studies was as follows:(1) The interpretation of the existing geoelectric data;(2) application of geophysical methods for non-destructive reconnaissance and their integration into a Geographic Information System(GIS). The analysis demonstrates that: The map of the isohypses and the geoelectric cross-section of the substratum of the superficial roof aquifer show clearly a plunge associated with development of the Paleozoic roof in the South and the direction of flow of the surface water is from south to north, from the upper zone to the north of the El Kansera dam. These conclusions constitute very useful contribution for any resource management projects in this area.  相似文献   
40.
The North-Pyrenean Front overthrust in northern direction was particularly active during the Upper Cretaceous, before the Upper Eocene tectonic renewal. Indeed, in the Eastern Pyrenees (Aude), ‘Garumnian’ (continental Upper Cretaceous–Palaeocene) formations lie transgressively upon the North-Pyrenean Triassic (Keuper) formation and upon the Albian beds of the Sub-Pyrenean Cucugnan slice. Relations between the North-Pyrenean Frontal Thrust and, to the northeast, the Corbières Nappe are discussed. To cite this article: A. Charrière, M. Durand-Delga, C. R. Geoscience 336 (2004).  相似文献   
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