عنوان مقاله [English]
This paper presents the effective processes on the oil slick after spill accidents in sea. Processes include advection, evaporation, dissolution, photo-oxidation, sedimentation and biodegradation which are described by analytical methods. The processes can influenc and change the initial parameters of oil, including density, water content and viscosity. Spreading process play a governing role during a period of several hours after spill accidents, while the process of transforming oil slick may occur during a period of several days. Estimation of evaporation, advection and the thickness of the oil layer is used in calculating the ratio of the natural dispersion by numerical models. The evaporation and the thickness determine the lifetime of oil slick on the sea surface by many models. In addition, estimates of the layer area of the slick can be used to evaluate efficiency of oil spill control methods and evaluation of their environmental impacts. The study was performed in the Assalouyeh marine region on the northern coasts of Persian Gulf, for effective processes on the fate of gas condensate slick. The results show that after spill accidents, the gas condensates transfer into the atmosphere due to evaporation and atmospheric and marine conditions, and also penetrate in the water column. Due to wind velocity, gas condensates move away from the coast in the winter and in summer due to higher stability at sea, gas condensate particles can accumulate on the surface (especially for larger particles).