川东北碳酸盐岩地层异常压力随钻监测方法

川东北碳酸盐岩地层具有高压和高含硫化氢的特点，严重威胁到钻井安全。针对其地层异常压力随钻监测困难的问题，从实测地层压力的纵向分布特点出发，深入揭示了异常压力的成因机制与录井参数响应特征;在对异常压力随钻监测理论与方法进行厘定的基础上，分别建立起孔隙型碳酸盐岩地层和裂缝型碳酸盐岩地层的异常压力随钻监测模型。这两个模型综合考虑了不同储集空间类型与增压机制、降压机制之间的关系，高压气层、高压水层的不同响应，以及自源成因与它源成因的影响，因而更加科学、合理，并在实际应用中取得了较好的效果。

Detection of abnormal pressure while drilling in carbonate formations of northeastern Sichuan Basin

High pressure and high hydrogen sulphide in carbonate formations of northeastern Sichuan Basin are a serious threat to drilling safety. The detection of abnormal pressure while drilling is regarded as a long-term difficult problem due to its complicated origin. In order to solve this problem, we investigated the genetic mechanism of abnormal pressure and the response of surface logging parameters and established detection models, respectively, for abnormal pressure while drilling either in porous-type or in fractured-type carbonate formations through theoretically and methodologically delineating the detection of abnormal pressure while drilling. These two models synthetically take various factors into consideration, such as the correlation between different accumulation capacity and pressurizing or depressurizing mechanism, the different response of high-pressure gas or water layers and the effect of autochthonous or allochthonous abnormal pressure, therefore, the application of these two models indicates that they are more scientific, reasonable and effective.