SINGAPORE, Oct 10 (Reuters) - Sentiment in the Asia-Pacific crude market weakened on Wednesday as a prompt Vietnamese crude offer surfaced after the country's only refinery was unexpectedly shut. Glencore offered 600,000 barrels of Bach Ho crude for October delivery after the 135,000 barrels per day refinery in Vietnam was shut on a glitch at a gasoline-making unit. More prompt cargoes are likely to appear as Vietnam will have to sell at least 1.9 million barrels of crude if the Dung Quat refinery is down for two weeks. "This is a prompt cargo and to place this cargo they have to give a good price," a trader said. * TRADES - Trafigura has sold 200,000 barrels of Rang Dong crude for December loading to a North Asian refiner at $2.70 a barrel above dated Brent, down from a premium of just above $3 for a November cargo. The European trader had bought the cargo on a term basis from PV Oil at $2.60 a barrel above dated Brent. * TENDERS - Vietnam's PV Oil has offered Su Tu Den crude for loading between January to June to be priced on dated Brent, completing a switch to the price reference for all its grades, a trade source said. The producer responded to calls from buyers to move away from a volatile regional reference - the Minas formula, an average of assessments from Platts and the Asia Petroleum Price Index (APPI) - by pricing all its grades on dated Brent. In the tender, buyers will have to submit their bids to buy a minimum 6,700 barrels per day (bpd) of the medium sweet Su Tu Den crude. The tender will close on Oct. 12 with bids valid until Oct. 23. - PV Oil also offered 200,000 barrels of Rang Dong crude for loading on Dec. 23-29 in a tender to close on Oct. 16 with bids valid until a day later. - Indian refiner HPCL is seeking up to 1 million barrels of sweet crude for December loading. The tender will close on Oct. 15 and remain valid until a day later. * MARKET NEWS - Asia's top refiner, China's Sinopec, has started work to build Southeast Asia's largest oil storage terminal at the Batam free trade zone in Indonesia, the company and industry sources said, in an $850-million investment aimed to boost petroleum trading. - Insurgents said they shelled the main city in Sudan's oil-producing South Kordofan state near the border with South Sudan on Wednesday, the second time this week. - Chevron's key crude unit at its oldest refinery in Richmond, California, would remain offline through the fourth quarter after it was badly damaged in an Aug. 6 fire. CRUDE Price Prev Change NOV Brent 114.49 112.54 +1.95 NOV Brent/Dubai EFS DUB-EFS-1M 4.59 4.20 +0.39 PRODUCT CRACKS NOV fuel oil crack -8.13 -9.69 +1.56 NOV gasoil crack 19.67 19.58 +0.09 NOV naphtha crack -7.60 -7.76 +0.16 COMPLEX REFINERY MARGINS Today 10.33 Last 5 days 9.40 Last 365 days 7.37 (Reporting by Florence Tan; editing by James Jukwey)

Source