Abstract
Unconventional resources are considered to be the game changer of near-by future energy. The huge resources of unconventional gas worldwide along with the increasing oil demand make the contribution of unconventional gas to be critical to the world economy. However, major challenges that operators face to produce from unconventional resources are due to the need for identifying a sweetspot, commercial stimulation technique that creates sufficient stimulated reservoir volume, very low permeability and different damage mechanisms such as water blocking, filtrate invasion during drilling, completion, stimulation or production.
This paper describes a new stimulation technique that creates synthetic sweetspot by thermal and mechanical energies. An energized fluid was used to generate localized heat and pressure in tight core samples and therefore create microfracturing. Created microfractures significantly increased permeability, porosity, and stimulated reservoir volume. A synthetic sweetspot nearby a wellbore or fracture area can be created by the new treatment mechanism. Permeability of tested cores was measured by Coreflood system and showed significant increase with new treatment technique. Communication between micro and macro pores was also found as a result of the treatment.
The treatment doesn't utilize any hydrocarbons and have no lift overs or potential damage. The generated high temperature and pressure can remove any damaging material or condensate banking near wellbore or fracture area. The new treatment technique was evaluated using Coreflood system with actual tight core samples collected from tight reservoirs in Saudi Arabia. NMR and CT-Scan analysis were used to show creation of microfracturing and permeability porosity changes.
