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The cyclone is expected to be worse than one that hit Oman's Masirah Island in 1977. (NASA/GSFC)
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Oil surged above $70 on Monday on news a cyclone had potential to disrupt shipping and output. (Graphic: Craig Willers, ITP Digital)
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In 1977 a similar storm hit Masirah Island, just off the coast of Oman, when 400mm of rain fell in 24 hours.
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Despite militants calling a one-month truce in attacks on oil installations in the Niger Delta, output disruptions in Nigeria continue to tighten supply. (Picture, dated 13 April 2007, shows a militant group in Nigeria - LIONEL HEALING/AFP/Getty Images)
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Thick clouds over Muscat. Cyclone Gonu was packing winds of up to 260 kilometres an hour. (MOHAMMED MAHJOUB/AFP/Getty Images).
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The storm could prompt massive evacuation of residential areas as far inland as 10km.