岩石可钻性与地层孔隙压力关系的测井研究

岩石可钻性是钻头选型和钻速预测的重要参数.岩石可钻性与其声波时差有着密切的关系.地层孔隙压力在一定程度上可由测井声波时差来反映.若能建立岩石可钻性与地层孔隙压力之间的定量关系,就可由地层孔隙压力对岩石可钻性进行实时预测.鉴于此,从测井估算地层压力的等效深度法和岩石可钻性模型出发,推导了岩石可钻性与地层孔隙压力的理论关系模型,并利用川东渡口河构造的Du4井和S油田实际资料建立了两者间的回归统计模型,进一步印证了该理论关系的正确性,为利用地层孔隙压力实时预报岩石可钻性提供了依据,也为岩石可钻性的测井解释找到了一条新的途径.

On Relation Between Rock Drillability and Formation Pore Pressure from Log Data

The rock drillability is the important parameter of selecting the bit types and predicting drilling rate. The rock drillability has close connection with sonic interval travel time and formation pore pressure can be reflected by it in some degree. If the quantitative relation between the rock drillability and formation pore pressure can be determined, the former will be predicted from formation pore pressure data in real time. Whereas, we have deduced the theoretic relation model from rock drillability model and equivalent depth method for formation pressure estimation, and by making full use of the practical data of Du4 well and S oilfield, this relation is further verified. This relation provides foundation for predicting rock drillability through formation pore pressure. Moreover, it provides a new approach to interpret rock drillability from logging data.