在碳酸盐岩地层应用欠压实原理，会使异常压力随钻监测成为威胁钻井安全的一道难题。为了解决该类地层异常高压随钻监测理论、异常高压识别、监测模型选择等关键问题，以川东北飞仙关组和长兴组地层实测压力的纵深分布特征为基础，通过与东营凹陷碎屑岩地层压力分布特征对比，指出基于上覆压力梯度的地层压力随钻监测方法并不适用于碳酸盐岩地层。在理论探讨的基础上，从岩石成分及应力敏感性角度，解释了硫酸盐热化学还原反应和构造挤压是造成高压地层与常压地层识别标志差异的主要原因。孔隙型碳酸盐岩地层和裂缝性碳酸盐岩地层的压力演化历程不同，其监测模型也不同，为此对压力监测模型中的孔隙与裂缝识别、气层和水层识别给出了具体的区分方法。上述几个关键问题的探讨，有助于提高对碳酸盐岩地层异常压力的认识与预测监测水平。%Uncompaction theory is not suitable for carbonate formations ,if this theory is used in car-bonate formations ,abnormal pressure detection while drilling will be wrong ,bringing about threat to drill-ing safety .In order to solve abnormal pressure detection theory and methods ,and monitoring model selec-tion etc ,based on the comparison between the vertical distribution of test pressure data in Feixianguan and Changxing Formation in Northeastern Sichuan Basin ,and the distribution of formation pressure of clastic rocks in Dongying Sag ,it is was pointed out formation pressure detection while drilling based on the over-burden pressure gradient was not suitable for carbonate formations .It was explained that the identification marks between high pressure layer and normal pressure layer were caused by TSR reaction and tectonic compression .The pressure detection models of porous-type reservoirs and fracture-type reservoirs were dif-ferent due to different evolution course of formation pressure ,so this paper provided the methods to distin-guish porous and fracture carbonate reservoirs ,gas layers and water layers .The study above could improve the recognition of carbonate formation pressure and the level of pressure prediction and detection .
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