Abstract:

The tight oil reservoir in the Jinlong 2 well block in the Zhongguai bulge, western uplift of the Junggar Basin, is developed by horizontal well hydraulic fracturing. Frequent inter-well frac-hit caused by the large-scale well infilling and the presence of fault zones in the reservoir impedes production efficiency greatly. By investigating the applicability of monitoring and identification methods for inter-well frac-hit in multi-stage fractured horizontal wells, and combining field fracturing monitoring and production data from the Jinlong 2 well block, a comprehensive identification workflow for inter-well frac-hit was established. This workflow which integrates production performance, fracturing operation, and microseismic characteristics was used to identify and analyze inter-well frac-hit in the study area. The results show that severe inter-well frac-hit exists in the Jinlong 2 well block, not only within but also across individual horizons and fault blocks. The relatively small horizontal well spacing and developed fault system in the reservoir in the Jinlong 2 well block may induce inter-well frac-hit. It is recommended to avoid well infilling in large-scale fault zones and reduce fracturing scale for infill wells.

Key words: Junggar Basin, western uplift, Zhongguai bulge, upper Urhe formation, tight oil reservoir, horizontal well, hydraulic fracturing, inter-well frac-hit