This thesis presents the results of phase behavior calculations and simulation of asphaltene precipitation, flocculation, and deposition in five wells from Saudi Arabia and UAE, for the first time. Asphaltene precipitation becomes a serious problem especially when it causes plugging of the formation, wellbore, or production facilities. Asphaltene prevention techniques are discussed in details and supported by simulated case studies for the five wells. Asphaltene precipitation was modeled by using WinProp (a phase behavior utility from CMG) which uses Nghiem solid model. Asphaltene...