The injected fluids in secondary processes supplement the natural energy present in the reservoir to displace oil. The recovery efficiency mainly depends on the mechanism of pressure maintenance. However. the injected fluids in tertiary or enhanced oil recovery (EOR) processes interact with the reservoir rock/oil system. https://www.bekindtopets.com/hot-save-Original-German-Pre-WWI-Gewehr-91-S-Artillery-Carbine-by-V-C-Schilling-Serial-7911-b-with-Replaced-Kar-88-Stock-Dated-top-savings/