Investigation of Formation Damage and Well Injectivity by Injection History during Water Injection Process

The histroy of water injection is a cheap and useful tool to investigate well injectivities in lack of laboratory experiment during a water injection project. This paper tries to evaluate near wellbore formation damage qualitatively through an efficient technique using minimum available information of an injection well like injection pressure, injection rate and the time period of injection. Here, the performances of water injection wells of one of the Iranian oilfields have been evaluated in respect of formation damage and fracture propagation benefiting the changes in slope of cummulative pressure-time versus cumulative injected water as well as instantaneous pressurerate plot. Finally, employment of this approach for analysis of formation failure and thermal stresses created within the first steps of injection process is recommended.