The research of overpressure prediction and detection has long been concentrated on under-compaction, the overpressure originated from hydrocarbon generation was thought difficult and even impossible to be predicted and detected. In order to predict and detect the pressure originated from hydrocarbon generation, we compared the characteristics of under-compaction strata with that of source rocks, and studied the changing of pressure caused by hydrocarbon generation with depth. The results show thai the so-called under-compaction actually is the combined response of genuine under-compaction and hydrocarbon generation, the pressure generated by hydrocarbon generation could also be predicted and detected while drilling. Based on that, the method distinguishing their contribution and the predicting and detecting methods, such as exponent and neural network, are put forward. This research result renew the viewpoint that the overpressure originated from hydrocarbon generation couldn't be predicted and detected, so, it contributes to improve geology understanding about overpressure and the level of overpressure prediction and detection.%长期以来,对异常高压预监测的研究集中在欠压实成因上,认为烃类生成成因的异常高压是难以预监测,甚至是不可预监测的.为实现生烃超压的预监测,对生烃地层和欠压实地层的测录井参数响应特征进行了对比,并对烃类生成所产生的异常高压随井深的变化规律进行了研究,结果表明:生烃地层在中子密度、声波时差、地层可钻性指数等方面的响应特征跟欠压实地层是一致的,且其生成的异常高压随井深增加也呈规律性变化；地层可钻性指数等方法所预监测的地层压力并不仅仅是欠压实成因的,也包括生烃增压的贡献.在此基础上,提出了二者贡献的区分方法及将地层可钻性指数与烃类体积响应参数结合在一起的综合性指数和BP神经网络2种超压预监测方法.该研究打破了生烃超压不可预监测的观点,有助于提高对异常高压的地质认识和随钻预监测水平.
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