HONG KONG, April 16, 2012 /PRNewswire-Asia/ -- CNOOC Limited (the "Company", NYSE: CEO, SEHK: 00883) today announced that the Company has successfully appraised the Penglai(PL)9-1 hydrocarbon bearing structure following the discovery made in 2010. The appraisal confirmed that PL9-1 is a large oilfield. (Logo: http://www.prnasia.com/sa/200701301659.jpg ) PL9-1 is located in the Miaoxibei uplift in the eastern part of Bohai, with an average water depth of 25 meters. One of the appraisal wells PL9-1-5 encountered oil pay zones in buried hill with total thickness of over 200 meters, and the well was tested to produce around 700 barrels of oil per day. PL9-1 is the largest oilfield among the recent years' discoveries by scale in Bohai. Furthermore, the Company also made a successful discovery of PL15-2 structure, located 8 kilometers south of PL9-1.The discovery well of PL15-2-1 encountered oil pay zones with total thickness of 83 meters, and the test indicated an average rate of over 1,200 barrels of oil per day. Mr. Li Fanrong, CEO of the Company commented, "I am delighted the Company has successfully appraised another large discovery in offshore China. I believe the successful appraisal on PL9-1 will open up a new prospect for exploration and development in Eastern Bohai waters as well as make great contribution to maintain steady production in Bohai region." - End - Notes to Editors:More information about the Company is available at http://www.cnoocltd.com. *** *** *** *** This press release includes "forward-looking statements" within the meaning of the United States Private Securities Litigation Reform Act of1995, including statements regarding expected future events, business prospectus or financial results. The words "believe", "intend", "expect", "anticipate", "project", "estimate", "plan", "predict" and similar expressions are intended to identify such forward-looking statements. These statements are based on assumptions and analysis made by the Company in light of its experience and perception of historical trends, current conditions and expected future developments, as well as other factors that the Company believes reasonable under the circumstances. However, whether actual results and developments will meet the Company's expectations and predictions depends on a number of risks and uncertainties which could cause the actual results, performance and financial conditions to differ materially from the Company's expectations, including those associated with fluctuations in crude oil and natural gas prices, the exploration or development activities, the capital expenditure requirements, the business strategy, the highly competitive nature of the oil and natural gas industries, the foreign operations, environmental liabilities and compliance requirements, and economic and political conditions in the People's Republic of China. For a description of these and other risks and uncertainties, please see the documents the Company has filed from time to time with the United States Securities and Exchange Commission, including 2010 Annual Report on Form 20-F filed on April 29, 2011. Consequently, all of the forward-looking statements made in this press release are qualified by these cautionary statements. The Company cannot assure that the actual results or developments anticipated will be realized or, even if substantially realized, that they will have the expected effect on the Company, its business or operations.