Sundance Cruises, Eastern Cruise Lines and Western Cruise Lines will operate their three ships - Stardancer, Emerald Seas and Azure Seas - under one new corporation, effective October 1.

GotaasLarsen Shipping Corp. - parent company of Eastern/Western will own 51 percent of the new corporation, which has not yet been named. The owners of Sundance - Johnson Line and Effoa - will hold 24.5 percent each.

Bernard Chabot, president and chief executive officer of Eastern/Western, will serve as president. Stanley Mcdonald, president of Sundance Cruises will serve as co-chairman, along with Richard Fain, the marketing director of GotaasLarsen. The merger gives the new company, a capacity for about 2,700 passengers, and footholds in the three-, four- and seven-day markets.

Under the new corporation, the three ships will continue to offer their current itineraries. Stardancer will remain based in Seattle, offering seven-day cruises to Mexico during the fall, winter and spring, and cruises to Alaska in the summer. Emerald Seas will continue to offer her three- and four-day sailings to the Bahamas out of Miami, while the Azure Seas remains in Los Angeles, featuring three- and four-day cruises to Mexico.

Reservations will be based in Miami and Los Angeles - where Eastern and Western are headquartered, respectively. Sundance's Seattle office is being phased out.