A pilot project was initiated by PetroChina-Changqing to test a new integrated drilling and fracturing solution for a tight oil reservoir in central China. The results indicated this new integrated solution is an effective way to access the tight oil with high production, even with permeability less than 0.2 md. The integrated solution included a horizontal well drilled with real-time image and near-bit measurements for accurate and timely well placement decisions, well placement technology for trajectory optimization, multistage fracturing technology to stimulate the tight reservoir, and a properly placed trajectory and updated geologic model to optimize the fracture design.
With good cooperation between the service company and the operator, this pilot project showed favorable production results. Production testing on the first horizontal well showed initial production of 120 m3/day in contrast to the vertical well production of less than 1 m3/day. The real-time image clearly indicated the trajectory position in the sand and provided confirmed information for accurate trajectory adjustment. Well placement technology was successfully applied in the tight oil reservoir, with net-to-gross KPI of 100%, and the well trajectory placement met the specific exploration purpose. A 14-stage fracturing job was successfully executed, with 65% of the fluid volume flowback.
Microseismic monitoring indicated that all of the intended reservoir was stimulated. The pilot project showed that the integrated drilling and fracturing solution using horizontal well technology was effective for a tight oil reservoir. This solution can be applied to other tight oil blocks to improve tight oil exploration and development.