Japan's Maruzen Petrochemical said on Friday it shut its sole naphtha cracker at Chiba, east of Tokyo, with capacity to produce 480,000 tons per year of ethylene, after a strong earthquake.

Maruzen's Keiyo Ethylene unit also shut a 690,000 tpy naphtha cracker in Chiba after the quake, a Maruzen spokesman said.

Keiyo Ethylene is 55%-owned by Maruzen Petrochemical and 22.5% each by Mitsui Chemicals and Sumitomo Chemical.