Chengdao oil field is located in the southern part of Bohai Bay, China. It lies 5km far from the seashore, where the depth of the sea water is less than 15m. It was discovered in 1988 by well Chengbei-12. Due to peculiar geographical situation, abominable environment and climate, complicate reservoir characteristics and high economic risk of exploration and development, Chengdao oil field belongs to super shallow sea marginal oil field category.
Based on maritime engineering, recovery technology, revenue policy, geological and recoverable characteristics of upper Guantao sandstones, which are the major oil-bearing series of Chengdao Oil Field, Log- Constrained Seismic Inversion technique and 3D visual geological model establishment technique are combined to establish 3D conceptual model and static model in different initial development stage. Then geostatistics, numerical simulation and economic evaluation techniques are applied to optimize and determine reservoir engineering technical limits, such as development scheme, well pattern and spacing, timing of water injection, water injection scheme and injection-to- production ratio, in order to reduce economic risk of developing these marginal resources effectively.
Research results have been applied comprehensively, and notable economic benefits have been obtained practically. During 1996–2001, cumulative oil productivity of upper Guantao reservoir in pure natural energy development period had increased to 714 ×104t with sales revenue85.3 ×108 ¥ and net profits11.5 ×108 ¥. Research results are provided with comprehensive popularized prospect still, and can provide theoretic foundation and practical reference for development of these similar marginal oil fields.
Chengdao oil field is one of the greatest Chinese neritic marginal oil field. It is situated in the north of Dongying city of Shandong province, China. It was discovered in 1988 by the well CB12. Now, it possesses the proved oil-bearing area of more than 100Km2, with about 3?108t of OOIP. Its pay zones are composed of six formations, from top to bottom, which are Minghuazhen formation, upper Guantao (Ng) formation, Dongying formtion, Shahejie formation, Mesozoic Earthen, Palaeozoic Earthen and Archaeozoic Earthen. Among them upper Ng sandstones are the major oil-bearing series and covers 89.6% OOIP of all, and are the developed target.
Although having been discovered for 14 years, Chengdao Oil Filed has developed slowly due to the actual difficulties in the development course, such as peculiar geographical situation, abominable environment and climate, complicate reservoir characteristics and high economic risk of exploration and development. In order to develop the major oil-bearing sandstones, upper Ng reservoir reasonably and economically, some tentative techniques are applied to optimize and determine reservoir engineering technical limits.
Chengdao oil field is located in the super shallow sea of southern part of Bohai Bay, China. It lies 5km far from the seashore, where the depth of sea water is less than 15m. It is adjacent to the Zhuangxi and the 5th picket oil field in the south, which belong to alongshore oil fields. And it is 35km far away from another northwestern maritime oil field, Chengbei oil field (Fig. 1).