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121.
The static modeling and dynamic simulation are essential and critical processes in petroleum exploration and development. In this study, lithofacies models for Wabiskaw Member in Athabasca, Canada are generated by multipoint statistics(MPS) and then compared with the models built by sequential indicator simulation(SIS). Three training images(Tls) are selected from modern depositional environments;the Orinoco River Delta estuary, Cobequid bay-Salmon River estuary, and Danube River delta environment. In order to validate lithofacies models, average and variance of similarity in lithofacies are calculated through random and zonal blind-well tests.In random six-blind-well test, similarity average of MPS models is higher than that of SIS model. The Salmon MPS model closely resembles facies pattern of Wabiskaw Member in subsurface. Zonal blind-well tests show that successful lithofacies modeling for transitional depositional setting requires additional or proper zonation information on horizontal variation, vertical proportion, and secondary data.As Wabiskaw Member is frontier oilsands lease, it is impossible to evaluate the economics from production data or dynamic simulation. In this study, a dynamic steam assisted gravity drainage(SAGD)performance indicator(SPIDER) on the basis of reservoir characteristics is calculated to build 3 D reservoir model for the evaluation of the SAGD feasibility in Wabiskaw Member. SPIDER depends on reservoir properties, economic limit of steam-oil ratio, and bitumen price. Reservoir properties like porosity,permeability, and water saturation are measured from 13 cores and calculated from 201 well-logs. Three dimensional volumes of reservoir properties are constructed mostly based on relationships among properties. Finally, net present value(NPV) volume can be built by equation relating NPV and SPIDER. The economic area exceeding criterion of US$ 10,000 is identified, and the ranges of reservoir properties are estimated. NPV-volume-generation workflow from reservoir parameter to static model provides costand time-effective method to evaluate the oilsands SAGD project.  相似文献   
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We examined the infiltration pattern of water in a regolith–bedrock profile consisting of two overburdens (OB1 and OB2), a buried rice paddy soil (PS), two texturally distinctive weathered materials (WM1 and WM2) and a fractured sedimentary rock (BR), using a Brilliant Blue FCF dye tracer. A black‐coloured coating in conducting fractures in WM1, WM2 and BR was analysed by X‐ray diffraction and scanning electron microscopy. The dye tracer penetrated to greater than 2 m depth in the profile. The macropore flow and saturated interflow were the major infiltration patterns in the profile. Macropore flow and saturated interflow were observed along fractures in WM1, WM2 and BR and at the dipping interfaces of PS–WM1, PS–WM2 and PS–BR respectively. Heterogeneous matrix flow occurred in upper overburden (OB1) and PS. Compared with OB1, the coarser textured OB2 acted as a physical barrier for vertical flow of water. The PS with low bulk density and many fine roots was another major conducting route of water in the profile. Manganese oxide and iron oxide were positively identified in the black coating material and had low crystallinity and high surface area, indicating their high reactivity with conducting contaminants. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
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Understanding the patterns of microbial diversity and their composition in seawater is necessary to assess the impacts of microbes on marine ecosystem. Although the potential roles of microbes in the ocean have been studied, their diversity and relationship with environmental factors remain unclear. In this study, we adopted a 16S rRNA gene tag-pyrosequencing technique to investigate the bacterial communities associated with two different water masses from Tongyoung in the South Sea of Korea. Our results revealed highly diverse bacterial communities up to 900 Operational Taxonomic Units (OTUs) estimated from each seawater which was collected in the month of March and May, when the environmental conditions including temperature differed significantly: 7.2°C and 17.6°C in March and May, respectively. Altogether, 13 bacterial phyla were recovered from the seawater, of which Proteobacteria was the most dominant group. In addition, the value of the Shannon index, which measures the evenness of the distribution of individuals among OTUs, in May is higher than that in March, indicating that it displays a wider diversity of bacteria. Interestingly, the proportion of pathogenic bacteria was significantly increased in the month of May compared to March, suggesting that pathogenic bacteria were increasingly emerging in May. In particular, Pseudoalteromonas and Vibrio spp. were determined as major pathogenic bacteria from both water masses, of which Vibrio spp. were dominant.  相似文献   
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In the heavily industrialized Masan Bay of southern coast, Korea, the potential harmful effects of heavy metals (Cd, Co, Cu, Ni, Pb, Sn, Zn, and Hg) were evaluated in terms of the pollution load index (PLI) and ecological risk assessment index (ERI) methods, and the results obtained were considered alongside the health of the macrobenthic fauna communities. The results revealed that the bay sediments, especially in the inner bay and the outfall area of a sewage treatment plant, are exposed to moderate to serious levels of metal pollution. Hg and Cd contributed the most to the potential toxicity response indices in sediments recently deposited in the bay. The potential ecological risk assessment of heavy metals in the bay was highlighted by the use of the benthic biological pollution index (BPI), suggesting that the ERI is a useful toxicity response index, which can quantify the overall ecological risk level to a target environment.  相似文献   
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Military shooting range soils contaminated by heavy metals have been subjected to remediation efforts to alleviate the detrimental effects of exposure on humans and the surrounding environment. Waste materials can be used as cost-effective soil amendments to immobilize heavy metals in contaminated soils. In this study, naturally occurring lime-based waste materials including egg shells, oyster shells, and mussel shells were assessed for their effectiveness toward heavy metal immobilization in military shooting range soil in Korea. Soil was treated in batch leaching experiments with 0, 2.5, 5, 10, and 15% of each lime-based waste material. The results showed that the lime-based waste materials effectively reduced water-soluble Pb at an application rate of 2.5% by weight of the soil. Increase in soil pH from 6.6 to 8.0 was considered to be the main chemistry of Pb immobilization, which was supported by the formation of insoluble Pb species at high pH values as confirmed by the visual MINTEQ thermodynamic model. In contrary, water-soluble Cu was increased in the lime-based waste material-treated soils when compared to the untreated soil. This was likely attributed to the formation of soluble Cu?CDOC (dissolved organic carbon) complexes as all lime-based waste materials applied increased DOC contents in the soil. Therefore, care must be taken in selecting the appropriate amendment for immobilizing metals in shooting range soils.  相似文献   
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A radial collector well is used for the extraction of a large amount of groundwater without causing a deep drawdown at the well??s center, and it is appropriate for the supply of municipal water through riverbank filtration (RBF). Flow path changes caused by water extraction through a radial collector well were simulated to estimate the amount of river water induction at a RBF site associated with Nakdong River in South Korea. The structure of the screened horizontal arms of a radial collector well was examined with respect to effective riverbank filtration. The relative ratio of the river water induced to the radial collector well compared to the total groundwater extraction was estimated to be 27?C52%. The amount of induced river water varies with the distance of a horizontal arm from the river, indicating that the location and structure of the collector well is significant for RBF. In all simulation cases, the maximum drawdown of the groundwater level near the collector well was 2.1?m, which is not significant considering the substantial pumping rate at the study site. It was concluded that RBF radial collector wells can be used at the study site for a sustainable water supply.  相似文献   
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