Cost Effective Framework of Integrated Development of Offshore Marginal Oilfields - Case Study of a Heavy Oil Reservoir with Thin Layers

The Bohai bay is rich in oil and natural gas resources. Over the past 40 years, a series of different types of large and medium-sized offshore oil and gas fields have been successfully discovered and developed. The newly discovers, however, is marginal either smaller in size or poor in reservoir quality which can't be economically and efficiently developed with the current conventional exploitation methods. The development of such marginal assets is of great significant for the the sustainability of Bohai production. In this paper, L oilfield is taken as an example to explain how to establish a framework in developing such marginal oilfields cost-effectively through multi-disciplinary cooperation. The L oil field is one of the typical marginal green-oil fields discovered recently in the Bohai Bay which characterized as low OOIP, limited certain reservoir spaces for well placement and challenges economically for standalone development (Adeogun Oyebimpe, August 2018, Mohamed, A. Zakariya.March 2003). In addition, primarily thin oil layers at the average single layer thickness only 2.1 m, high crude oil viscosity at the average of 2000mpa·s, and low single well productivity less than 300 barrels per day. However, the L oil field geographically is next to a large oil field which is only 12km away. How to maximize the success chance of penetrating the sweet spot of those thin layers, and therefore achieve higher initial oil productivity, to form a complete injection-production well pattern for long period stability in production and to minimize capital investment through joint development with surrounding oilfields is the way out for L oilfield development.