Research and application of pre-monitoring technology of formation pressure with drilling——The example of the Bozi-Dabei area in the Krasu tectonic zone of the Kucha depression
Anomalously high pressures are common in sedimentary basins,and the Krasu tectonic zone in the Kucha fore-land basin has experienced multiple phases of tectonic movements,developed multiple pressure systems vertically,and the mechanism of over-pressure genesis is significantly differentiated,which makes drilling and construction of wells difficult.Therefore,accurate pre-monitoring of formation pressure is of great significance for drilling engineering parameters,mud per-formance,well structure optimization and safe and efficient drilling.Based on seismic,logging and drilling data research,this paper carries out the research on the mechanism of over-pressure genesis in the Krasu tectonic zone and the characteristics of longitudinal and transversal pressure distribution.Based on the traditional dc index pressure pre-monitoring method,the in-troduction of the full hydrocarbon correction coefficient innovates and optimizes the calculation model of the dc index,which improves the accuracy and timeliness,and through the on-site application of 10 wells,it is shown that the method has a high rate of conformity,with a relative error of 5.7%on the average.which is effective and suitable for complex formation and stra-tum,and can provide timely and effective scientific basis for Tarim Oilfield drilling site to avoid the risks of well leakage,stuck drilling and so on.
Kucha depressiontectonic zonestress forecastingpressure monitoringEaton's methoddc index
NETL
NSTL
万方数据
