NUMERICAL SIMULATION OF CURRENT-INDUCED DEFORMATION AND MOVEMENT OF THE OIL SLICK UNDER THE ICE COVER Yoshitaka Matsuzaki 1 , Toshinori Ogasawara 1 , Shigeki Sakai 1 Koh Izumiyama 2 and Shigeo Kanada 2 1 Iwate University, Morioka, Japan 2 National Maritime Research Institute, Tokyo, Japan ABSTRACT The full operation of crude oil and natural gas offshore the island of Sakhalin has just started. If oil spills accidentally, a coastal area along the Sea of Okhotsk in Hokkaido, Japan might suffer serious environmental damage from the spilled oil since there is a strong southward ocean current in the Sea of Okhotsk. The sea surface in this area is covered by ice in winter, therefore it would not be possible to find the spilled oil. In this study, a numerical simulation model is developed to predict the deformation and movement of an oil slick induced by a current under the ice cover. The validity of the model is examined by the comparisons with experimental results. And also, the effects of the current velocity, the amount of the spilled oil and the properties of the oil on the speed of the oil slick movement are discussed based on the numerical results. KEY WORDS: Oil; Ice; Current; Deformation and Movement; Numerical Simulation INTRODUCTION The full operation of crude oil and natural gas offshore the island of Sakhalin has just started. If oil spills accidentally, the coast area along the Sea of Okhotsk in Hokkaido, Japan might suffer serious environmental damage from the spilled oil since there is a strong southward ocean current in the Sea of Okhotsk as shown in Figure 1 (Wakatsuchi, 2001). The sea surface in this area is covered by ice in winter. If oil spills, the spilled oil spreads under the ice and drifts by currents to the coast area along the Sea of Okhotsk in Hokkaido. Therefore, it is necessary to examine the influences of currents on the oil slick under the ice. Proceedings oh the 18th IAHR International Symposium on Ice (2006) -219-