Aiming at the problem that the data-driven automatic correlation methods which are difficult to adapt to the automatic correlation of oil-bearing strata with large changes in lateral sedimentary facies and strata thic...Aiming at the problem that the data-driven automatic correlation methods which are difficult to adapt to the automatic correlation of oil-bearing strata with large changes in lateral sedimentary facies and strata thickness,an intelligent automatic correlation method of oil-bearing strata based on pattern constraints is formed.We propose to introduce knowledge-driven in automatic correlation of oil-bearing strata,constraining the correlation process by stratigraphic sedimentary patterns and improving the similarity measuring machine and conditional constraint dynamic time warping algorithm to automate the correlation of marker layers and the interfaces of each stratum.The application in Shishen 100 block in the Shinan Oilfield of the Bohai Bay Basin shows that the coincidence rate of the marker layers identified by this method is over 95.00%,and the average coincidence rate of identified oil-bearing strata reaches 90.02% compared to artificial correlation results,which is about 17 percentage points higher than that of the existing automatic correlation methods.The accuracy of the automatic correlation of oil-bearing strata has been effectively improved.展开更多
During the development phase horizontal wells are very efficient way to improve the production in the deep coal bed methane. The 8# coal seam in the XX block on the eastern edge of the Ordos Basin has challenges such ...During the development phase horizontal wells are very efficient way to improve the production in the deep coal bed methane. The 8# coal seam in the XX block on the eastern edge of the Ordos Basin has challenges such as deep burial depth (>2000 m), thin coal sweet spot (3 m), and significant short-distance structural fluctuations. The challenges caused a high risk of missing targets and running out of the target layers, as well as difficulties in cementing and completion due to uneven well trajectories. To address these challenges, this paper focuses on solving the issues through detailed precise geological modeling, optimized trajectory design, and accurate seismic geology Steerable Drilling. 1) Based on reasonable velocity field construction and Time-Depth transformation, a precise directional model is constructed using the layer-by-layer approximation principle with reference to marker layers, improving the accuracy of the target spot and avoiding premature or delayed entry into the target;2) Based on a precise geological model, the dip angle of the strata ahead and the development of sweet spots are clearly defined, enabling optimized trajectory design for horizontal wells;3) Using “1 + N” dynamic modeling to update the geological model in real-time during the drilling process, and actively guide the drill bit through the horizontal segment smoothly by using multi-information judgment of the drill bit position. The actual drilling of 80 completed horizontal wells in this area show: That this approach effectively ensures the smooth trajectory and high-quality drilling rate of the horizontal well in the coal seam, providing a basis for subsequent hydraulic fracturing and increasing single-well production. At the same time, it has certain potential value and significance for similar coalbed methane developments under similar geological conditions.展开更多
地面瞬变电磁资料解释精度的进一步提高一直是该方法研究的重点内容。以瞬变电磁烟圈效应扩散理论为依据,通过双倍旅程和平均速度概念建立了时深转换方法,以克服瞬变电磁采用简单经验公式计算实测数据时可能出现的深度翻转问题;以三维...地面瞬变电磁资料解释精度的进一步提高一直是该方法研究的重点内容。以瞬变电磁烟圈效应扩散理论为依据,通过双倍旅程和平均速度概念建立了时深转换方法,以克服瞬变电磁采用简单经验公式计算实测数据时可能出现的深度翻转问题;以三维地震成果数据获取的9号煤层深度作为电性标志层校正标准,采用视电阻率微分极值点识别该电性标志层,通过比值法计算相应瞬变电磁测点的深度校正系数 K 值,然后采用内插方法得到测区任意点 K 值,以校正瞬变电磁在计算探测深度时出现的偏差。通过堡子矿钻孔ZKB1-1和ZK201电阻率测井资料分别建立了正演理论模型,计算了瞬变电磁响应,并和钻孔旁瞬变电磁实测数据的视电阻率微分极值对比,结果表明,两者基本一致,能够准确识别电性分界面。以矿区256线和344测线为例说明了电性标志层识别效果,计算了堡子矿全区深度校正系数,对该区资料进行了精细处理,圈定了工作区奥灰顶低阻异常区,以视电阻率为基本参数,分析评价了该区的地层赋水性强弱。根据奥灰顶视电阻率平面图以及地表径流,结合断层构造的分布特征,确定了导水通道存在及位置。最后通过钻孔验证表明:该方法处理探测深度精度误差小于5%,达到了对地面瞬变电磁资料的精细解释。展开更多
基金Supported by the National Natural Science Foundation of China(42272110)CNPC-China University of Petroleum(Beijing)Strategic Cooperation Project(ZLZX2020-02).
文摘Aiming at the problem that the data-driven automatic correlation methods which are difficult to adapt to the automatic correlation of oil-bearing strata with large changes in lateral sedimentary facies and strata thickness,an intelligent automatic correlation method of oil-bearing strata based on pattern constraints is formed.We propose to introduce knowledge-driven in automatic correlation of oil-bearing strata,constraining the correlation process by stratigraphic sedimentary patterns and improving the similarity measuring machine and conditional constraint dynamic time warping algorithm to automate the correlation of marker layers and the interfaces of each stratum.The application in Shishen 100 block in the Shinan Oilfield of the Bohai Bay Basin shows that the coincidence rate of the marker layers identified by this method is over 95.00%,and the average coincidence rate of identified oil-bearing strata reaches 90.02% compared to artificial correlation results,which is about 17 percentage points higher than that of the existing automatic correlation methods.The accuracy of the automatic correlation of oil-bearing strata has been effectively improved.
文摘During the development phase horizontal wells are very efficient way to improve the production in the deep coal bed methane. The 8# coal seam in the XX block on the eastern edge of the Ordos Basin has challenges such as deep burial depth (>2000 m), thin coal sweet spot (3 m), and significant short-distance structural fluctuations. The challenges caused a high risk of missing targets and running out of the target layers, as well as difficulties in cementing and completion due to uneven well trajectories. To address these challenges, this paper focuses on solving the issues through detailed precise geological modeling, optimized trajectory design, and accurate seismic geology Steerable Drilling. 1) Based on reasonable velocity field construction and Time-Depth transformation, a precise directional model is constructed using the layer-by-layer approximation principle with reference to marker layers, improving the accuracy of the target spot and avoiding premature or delayed entry into the target;2) Based on a precise geological model, the dip angle of the strata ahead and the development of sweet spots are clearly defined, enabling optimized trajectory design for horizontal wells;3) Using “1 + N” dynamic modeling to update the geological model in real-time during the drilling process, and actively guide the drill bit through the horizontal segment smoothly by using multi-information judgment of the drill bit position. The actual drilling of 80 completed horizontal wells in this area show: That this approach effectively ensures the smooth trajectory and high-quality drilling rate of the horizontal well in the coal seam, providing a basis for subsequent hydraulic fracturing and increasing single-well production. At the same time, it has certain potential value and significance for similar coalbed methane developments under similar geological conditions.
文摘地面瞬变电磁资料解释精度的进一步提高一直是该方法研究的重点内容。以瞬变电磁烟圈效应扩散理论为依据,通过双倍旅程和平均速度概念建立了时深转换方法,以克服瞬变电磁采用简单经验公式计算实测数据时可能出现的深度翻转问题;以三维地震成果数据获取的9号煤层深度作为电性标志层校正标准,采用视电阻率微分极值点识别该电性标志层,通过比值法计算相应瞬变电磁测点的深度校正系数 K 值,然后采用内插方法得到测区任意点 K 值,以校正瞬变电磁在计算探测深度时出现的偏差。通过堡子矿钻孔ZKB1-1和ZK201电阻率测井资料分别建立了正演理论模型,计算了瞬变电磁响应,并和钻孔旁瞬变电磁实测数据的视电阻率微分极值对比,结果表明,两者基本一致,能够准确识别电性分界面。以矿区256线和344测线为例说明了电性标志层识别效果,计算了堡子矿全区深度校正系数,对该区资料进行了精细处理,圈定了工作区奥灰顶低阻异常区,以视电阻率为基本参数,分析评价了该区的地层赋水性强弱。根据奥灰顶视电阻率平面图以及地表径流,结合断层构造的分布特征,确定了导水通道存在及位置。最后通过钻孔验证表明:该方法处理探测深度精度误差小于5%,达到了对地面瞬变电磁资料的精细解释。