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451.
The ultimate goal of reservoir simulation in reservoir surveillance technology is to estimate long-term production forecasting and to plan development and management of petroleum fields. However, maintaining reliable reservoir models which honour available static and dynamic data, involve inherent risks due to the uncertainties in space and time of the distribution of hydrocarbons inside reservoirs. Recent applications have shown that these uncertainties can be reduced by quantitative integration of seismic data into the reservoir modelling workflows to identify which areas and reservoir attributes of the model should be updated. This work aims using seismic data to reduce ambiguity in calibrating reservoir flow simulation model with an uncertain petro-elastic model, proposing a circular workflow of inverted seismic impedance (3D and 4D) and engineering studies, with emphasis on the interface between static and dynamic models. The main contribution is to develop an updating procedure for adjusting reservoir simulation response before using it in the production forecasting and enhance the interpretive capability of reservoir properties. Accordingly, the workflow evaluates consistency of reservoir simulation model and inverted seismic impedance, assisted by production history data, to close the loop between reservoir engineering and seismic domains. The methodology is evaluated in a complex, faulted, sandstone reservoir, the Norne benchmark field, where a significant reservoir behaviour understanding (about the static and dynamic reservoir properties) is obtained towards the quantitative integration of seismic impedance data. This leads to diagnosis of the reservoir flow simulation reliability and generation of an updated simulation model consistent with observed seismic and well production history data, as well as a calibrated petro-elastic model. Furthermore, as Norne Field is a benchmark case, this study can be considered to enrich the discussions over deterministic or probabilistic history matching studies.  相似文献   
452.
An estimated 5.66 x 10(7) fish (summed quarterly 95% confidence intervals: 3.01 x 10(7)-1.07 x 10(8)) weighing 258.4 t (143.2-467.9 t) were killed on the cooling-water intake screens of the 2400 MW Longannet Power Station (Forth estuary) in January 1999--December 2000. Abundance and number of species (40) collected were close to predictions for a power station of this size and latitude. Potential losses of equivalent adult whiting (Merlangius merlangus), cod (Gadus morhua), and plaice (Pleuronectes platessa) through deaths of juveniles were estimated at 353.1 t (208.0-603.2 t) worth approximately euro 429,266 (euro 246,592-752,765) in 1999--2000. Fish catch-per-trawl in the estuary was generally not noticeably greater during a year of low water withdrawal (coal miners' strike of 1984--1985) when compared to other years from 1982 to 2001, except for gobies (Pomatoschistus spp.). A fish-return system is being tested at Longannet to reduce mortality.  相似文献   
453.
Vehicles cause environmental damage on sandy beaches, including physical displacement and compaction of the sediment. Such physical habitat disturbance provides a relatively simple indicator of ORV-related impacts that is potentially useful in monitoring the efficacy of beach traffic management interventions; such interventions also require data on the relationship between traffic volumes and the resulting levels of impact. Here we determined how the extent of beach disturbance is linked to traffic volumes and tested the utility of image-based data acquisition to monitor beach surfaces. Experimental traffic application resulted in disturbance effects ranging from 15% of the intertidal zone being rutted after 10 vehicle passes to 85% after 100 passes. A new camera platform, specifically designed for beach surveys, was field tested and the resulting image-based data compared with traditional line-intercept methods and in situ measurements using quadrats. All techniques gave similar results in terms of quantifying the relationship between traffic intensity and beach disturbance. However, the physical, in situ measurements, using quadrats, generally produced higher (+4.68%) estimates than photos taken with the camera platform coupled with off-site image analysis. Image-based methods can be more costly, but in politically and socially sensitive monitoring applications, such as ORV use on sandy beaches, they are superior in providing unbiased and permanent records of environmental conditions in relation to anthropogenic pressures.  相似文献   
454.
黄河小浪底水库抗震安全监测预测问题   总被引:1,自引:0,他引:1  
根据小浪底工程的实际特点 ,本文提出了黄河小浪底水利枢纽工程施工和运行期间抗震安全监测预测的一条思路。并对人工水体出现前、震情平稳期间、出现水库诱发地震期间、近场发生强烈地震期间等各阶段的工作提出了具体设想 ,准备在小浪底水库遥测地震台网开始实施.  相似文献   
455.
对地下采煤造成的地表沉陷进行及时、精确的监测监管是一个亟待解决的课题。该文以济宁市为例,介绍了D-InSAR技术在大范围采煤沉陷区监测及其时序变化特征分析中的应用。介绍了使用D-InSAR技术对采煤沉陷进行监测的基本原理;以5cm下沉线作为采煤沉陷区边界线,选取15期RADARSAT-2 Wide模式数据,采用多基线累积叠加方法分别提取各期采煤沉陷区边界并使用岩移观测数据对监测结果进行了检核。以花园煤矿为例,分析D-InSAR监测采煤沉陷范围及程度的时序变化特征,随着开采的持续进行,沉陷范围及沉陷量逐步增加,受临近工作面开采影响,沉陷中心的沉陷量呈周期性增加。结果表明,D-InSAR可以精确有效地对采煤沉陷区范围及其时序变形过程进行监测,可以应用于大尺度采煤沉陷区的动态监测。  相似文献   
456.
介绍了广东省地震局地震现场调查组在兴宁大兴煤矿ML1.4级塌陷地震的应急处理过程,叙述了应急小组从组网初步方案的实施到现场组网成功的经过,指出流动组网监测所取得的地震监测效益和社会经济效益,总结了经验和存在的不足.  相似文献   
457.
以示范性循环水养殖厂产生的废水为监测分析对象,采用在线连续监测和水样采集分析相结合的方法,观测了该养殖厂废水的化学特征,分析了影响水质的关键污染因子并探讨了其主要来源,同时对当前循环水养殖技术进一步发展亟需改进的关键技术环节进行了分析。结果表明,养殖废水中污染物的浓度与所养殖鱼的生长阶段相关;废水化学耗氧量变化受到其中悬浮物的影响,但化学耗氧量主要来源是水体中的溶解态物质;废水中的氮、磷污染物主要以溶解态存在,特别是无机形态。  相似文献   
458.
面向遥感监测的中国湿地区划初步构想   总被引:1,自引:0,他引:1  
遥感技术作为对湿地进行监测的现代空间信息技术,在对湿地研究和管理中日益发挥重要作用。我国国土面积广大,在不同地带分布有不同类型的湿地。现有的湿地分类工作尚不能满足对全国开展湿地监测的需要,也缺少地理区划理论的支持。为满足全国湿地遥感动态监测的需要,以现有湿地相关研究为基础,对湿地区划的指标体系、区划的原则、方法以及区划的等级体系进行了讨论,旨在为湿地区划方案的制定和实施提供参考。  相似文献   
459.
This study summarizes the relevant information regarding the spatial distribution of polychlorinated biphenyls (PCBs) in various environmental (e. g., soil, sediment, air, water) and biological (e. g., fish, mussel, adipose tissue, milk) media in Turkey. The information sources used for this purpose, in addition to the scientific literature, were; official import records, governmental reports on monitoring of organochlorines, and reports prepared by international organizations. PCBs were never produced in Turkey; however they were imported and used within equipment or otherwise. The number of studies conducted on the topic is increasing significantly throughout the years and especially in the last decade. Evidence of PCB pollution was compared with the available background monitoring results from the region and other parts of the world, as well as relevant legislative standards. Overall, the presence of a number of important local PCB contamination sources is indicated as a result of this assessment.  相似文献   
460.
A molecular PCR-based assay was developed and applied to macrophyte and seawater samples containing mixed microphytobenthic and phytoplanktonic assemblages, respectively, in order to detect toxic Ostreopsis species in Mediterranean Sea. The specificity and sensitivity of the molecular PCR assay were assessed with both plasmidic and genomic DNA of the target genus or species using taxon-specific primers in the presence of background macrophyte DNA. The PCR molecular technique allowed rapid detection of the Ostreopsis cells, even at abundances undetectable within the resolution limit of the microscopy technique. Species-specific identification of Ostreopsis was determined only by PCR-based assay, due to the inherent difficulty of morphological identification in field samples. In the monitoring of the toxic Ostreopsis blooms PCR-based methods proved to be effective tools complementary to microscopy for rapid and specific detection of Ostreopsis and other toxic dinoflagellates in marine coastal environments.  相似文献   
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