超低渗透油藏水驱效果因素

Analysis of influencing factors of water flooding effect in ultra-low permeability oil reservoirs

长庆油田超低渗透油藏2008年投入大规模开发，开发过程中部分油藏投产初期递减大、见效程度低、含水上升快等开发矛盾突出。为了改善油藏水驱效果，从沉积特征、储层特征、裂缝、井网、注采政策等方面进行综合分析，研究影响油藏水驱的主要因素。结果表明：沉积特性导致的油砂体宽度小、非均质性强是影响水驱状况的客观因素，开发中裂缝延伸是影响油藏水驱的主要及可控因素，开发技术政策及井网适配性影响油藏后期稳产。

The ultra-low permeahility reservoirs in Changqing Oilfieht were put in large-scale development in 2008. In the development process, glaring cnntradictions occur in some reservoirs such as a marked decline of production, low degree of oil-well response, large water-eut rising rate, etc.in the early stages of production. In order to improve the water-flooding effect, the main factors influeneing the water-flooding, such as sedimentary features, reservoir characteristics, fractures, well pattern, injectiun- production policy, welt comprehensively analyzed. The study results show that the small width uf oil sand body and strong heterogeneity caused hy sedimentary features are the objective factors affecting the water-flooding status; the fracture propagation during development is the main and controllable factor affecting water - flooding in the oil reservoirs; technical policy and well pattern suitability affect the later stage stable production.