歧北火成岩发育区下伏地层时深转换方法研究

Research on time-depth conversion method of the lower strata in the development zone of igneous rocks of Qibei

歧北火成岩发育区,火成岩速度大分布广,且厚度分布不均,时深转换将产生较大的误差,给落实构造和井位部署带来极大的困难。针对该区火成岩的发育特点,提出了速度填充结合厚度校正的方法,有效解决了火成岩发育区钻井预测深度误差较大的问题。从校正前、后的构造图对比可见,北部CFD1井附近火成岩较发育区域构造形态变化较大,向南构造形态变化逐渐变小,无火成岩的地方构造形态几乎没有变化。从验证井CFD2井馆陶组底面和东二上段底面预测深度与实钻深度对比可知,预测误差在10m以内,说明该方法的实用性和较高精度。利用该方法进行时深转换解决了CFD3井与CFD4井油水界面矛盾的问题,这也充分说明了该方法有效可行。

The igneous rock development zone of Qibei,the high velocity and variable thickness of igneous rock caused time-depth conversion producing a huge error,which leads to the construction being not implemented;this brings great difficulty for well deployment.By combining the characteristics of the development of igneous rocks in this area,this study proposed speed filling combined with thickness correction method to effectively solved the problem of the depth error of the drilling prediction of igneous rock area.According to the comparison of the corrected structure map,the structural change of the more development igneous rock area in the northern of CDF1 well around is larger,and from north to south the structural change become smaller,and there is no change where no igneous rock.From the comparison of the predicted depth and the drilling depth of the verification well CDF2's bottom surface of the Ng formation and E3d2l formation,The prediction error is less than 10 m,indicating that the new method has a higher precision.Using the new method for time-depth conversion solves the Between well CFD3 and well CDF4 Oil-water interface problem of contradictions,which fully shows the new method is effective and feasible.