Integrating Geology and Engineering for Viscous Oil Production Improvement—JX Oilfield, Bohai Bay, China

Abstract

In this paper a case study is presented where refined 3D reservoir geology models, well pattern pilot test and Real-time GeoSteering tools have been integrated to optimize production performance of a viscous oil reserve. The viscous reserves were of high structural dip angle. In addition delta depositional system represented highly variable geomorphology, where stacked sandbodies and shale bedding are crossing each other frequently. In order to keep a higher production rate, using horizontal wells along with water injection was not enough; therefore, detailed reservoir characterization, well pattern pilot experiment and GeoSteering were used to optimize previous development strategy and keep horizontal trajectories safely landing into reservoir target zone. The stratigraphic sequence architecture that is derived from seismic interpretations captured the variation within these high dip structural backgrounds very effectively. The best combination of choices was “Injecting Water outside from OWC” and “Stair Shaped Horizontal Trajectories”. The borehole collision risks of these optimized strategies were then analyzed and controlled successfully by the GeoSteering tools during trajectory landing process. The reservoir development performance is improved tremendously as result of these renewed development strategies.