Publications

This paper is intended to present an investigation of a hydraulic fracturing problem in the small fields of the Rokan Block asset. In order to optimize the oil production, the Operator undertook a hydraulic fracturing campaign in the small fields. Since based on historical results it needed high efforts in breaking the reservoir, during 2018 to 2019 almost half of the campaigns were postponed. The authors attempted to figure out a solution in fracturing the reservoir by implementing some of the common options utilized in the oil and gas industry (such as continuous pumping, acidizing, and re-perforate with big hole gun), and ultimately the reservoir fractured with hesitation pumping, which is a new method to break the formation, where repetition pumping performed to the maximum surface pressure limitation (hammering effect). The pre and post-frac fall-off pressure through G-function analysis indicated a Tortuosity effect. Compiling several historical hydraulic fracturing data of typical sands are required to have better understanding of reservoir issues by interpreting fall-off pressure data from mini fracturing through G-Function and Post Closure Analysis. Through these analyses, typical cases with near wellbore pressure loss (NWBPL) can be examined by performing output data matching with the reservoir properties, and it is also useful in fine tuning fracture treatment designs and execution. Furthermore, possible methods to resolve the NWBPL issue were listed, and then an experiment is carried out to determine which method is the most effective effort. In this study, the authors also carried out hydraulic fracturing operational lookback to differentiate jobs performed in the past, whether dominated by tortuosity issue or perforation friction, and to identify what effective proactive efforts were made. Moreover, the authors provide a comparison of several proactive efforts’ effectiveness: re-perf with big hole gun, acidizing and hesitation pumping. Based on those experiments, the authors conclude that the hesitation pumping effort is a new method that has proven to be effective in resolving the issue, and is even better than two other methods in term of the impact and the cost spending.