【摘要】 针对深水探井钻井可参考信息有限的特点,提出改进的计算上覆岩层压力梯度和建立时深关系的方法。利用概率统计理论,研究Eaton法中各个参数对最终结果的影响规律和相互关系,提出基于层速度的有效应力法与Eaton法联合预测地层孔隙压力的方法,建立了含有可信度的地层孔隙压力剖面,使其不再是一条单一的曲线,而是具有可信度信息的区间。可信度越大,得出的地层孔隙压力梯度区间越大,其不确定范围越大;反之,虽然压力梯度的不确定范围缩小,但其可信程度也随之降低;地层孔隙压力的异常高压程度越剧烈,其压力区间也越大。西非深水区域一口探井计算结果与实测压力值具有较好的一致性。更多还原

【Abstract】 For the lack of reference data from offset wells of deep water exploration well drilling,an improved approach to determining overburden pressure gradient was presented and the relationship of time and depth was established.With the probabilistic theory,the influence of each parameter on result and the interrelationship between them of Eaton model were studied.An approach to pore pressure prediction was provided by a combined methodology of Eaton model and effective-stress method using interval velocity data,and the pore pressure profile with credibility was established.This pore pressure profile is not a single curve but the interval with credibility information.Higher the credibility or the degree of overpressure,wider the interval of pore pressure gradient and the uncertainty area,otherwise,although narrower the uncertainty area,lower the credibility.The results of a well in West Africa deep water area agree well with the field test value.更多还原