Study of Thermally Assisted Gas Oil Gravity Drainage in One of Iranian Fractured Reservoirs

Naturally fractured reservoirs hold well over 100 billion barrels of heavy oil worldwide. For conventional reservoirs containing heavy oil, steam injection is the most widely used thermal recovery method. In heavy oil fractured reservoirs,steam injection is a challenging problem; however it is a potentially effective improved oil recovery method. In naturally fractured reservoirs containing gas filled vertical fractures, gas oil gravity drainage (isothermal gas oil gravity drainage) is an important recovery mechanism. In dipping fractured reservoirs with high fracture permeability, it may be possible to use steam to accelerate isothermal gas oil gravity drainage. This technique is a new and novel EOR technique known as Thermally (Steam) Assisted Gas Oil Gravity Drainage (TAGOGD (SAGOGD)). This study investigates the feasibility of steam injection and conducting TAGOGD technique in a highly fractured reservoir containing heavy oil in Iran. All data for this study are based on Kuh-e-Mund reservoir which is a highly fractured symmetrical anticline located in the southeastern part of Bushehr in the coast of Persian Gulf. The results of this study showed that this technique could improve oil recovery factor for this field.