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171.
二氧化碳地质封存环境监测现状及建议 总被引:5,自引:0,他引:5
CO2地质封存是应对全球气候变化的新举措,许多国家都开展了相关的工程项目或研究。环境监测作为验证场址在当前以及较长一段时间后的合理性和安全性的重要手段,是工程实施的重要工作。对国内外CO2地质封存环境监测的相关工作以及项目所采用的监测技术进行总结,并利用监测选择工具MST得出中石化胜利油田CO2-EOR项目适用的监测技术,在此基础上提出该项目背景监测的对象、技术和频率等框架,为项目监测工作的开展提供参考依据,最后简略提出环境监测工作的方法和大纲。 相似文献
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Tidal bore is hydraulic jump during the process of tide flooding with the tide wave moving upstream. They are widely distributed in the estuary zone with high tidal range and funnel-shaped planeform. Tidal bore deposit study is important for further understanding about paleogeomorphology, paleoenvironment, paleoclimate of areas near the estuaries, and sandbody formed by tidal bore deposit could be potential oil and gas reservoir. Researches about tidal bore have been always concentrated on hydraulic characteristics of tidal bore and its influences on estuary environment and engineering, while the study on tidal bore deposit is rarely reported. One of the most important causes is the complex hydrodynamic conditions in the estuary zone. Deposits characteristics is complicated in this zone due to comprehensive effects of river flow, waves and tides. It is hard to affirm the preservation probability of tidal bore deposits, especially in the ancient rock record. In view of this, current status and forecast about tidal-bore deposit study were expounded in this study based on comprehensive summary and discussion about typical tidal bore deposit data and reports. Criteria for recognition of tidal-bore deposits were described in detail on the aspects of sedimentary structures, grain size distribution, and facies model. One of the most critical diagnostic marks of tidal bore was a special undulating erosion surface with a series of irregular and stepped excavations on it. This surface was formed by cyclic pressure loading induced by the passage of a tidal bore. In addition, the cross-bedding inclined upstream, soft sediment deformation structures and massive sandstone on the erosion surface were also important marks of a tidal bore deposit. Problems existing in current research were discussed and some suggestions were proposed. Various methods and technology should be used to perfect tidal bore facies model, and research on diagenesis and reservoir features of sandbody formed by tidal bore should be strengthened in the future. Sandbody formed by tidal bore of different types (breaking tidal bore and undular tidal bore) should be distinguished to deepen the understanding of their various hydrodynamic conditions and reservoir scale. Tidal bore is significant geological process in estuary zone, and deposits formed by it makes great influence on the geomorphology of this area, which should be paid more attention. 相似文献
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定向钻进控制预测技术 总被引:9,自引:0,他引:9
定向钻井技术在矿产勘探及开发、煤层气开发中正发挥重大作用。准确预测定向钻井井底井斜和方位角,可降低定向钻井成本,减少定向钻进失误。目前使用的计算方法不利于现场快速准确预测井底轨迹。本文通过对井斜、方位与造斜工具角、造斜井长和造斜率的数据处理技术,建立了井底井斜和方位增量预测模型,与通用定向井公式比,精度高,且可在井场快速预测出定向钻井井底轨迹参数。经土耳其46对对接井实际证明,大大地提高井底预测速度和防止定向钻进失误率,对指导定向钻井现场快速预测具有指导意义。 相似文献
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