裂缝性低渗透砂砾岩油藏一体化评价方法及应用——以盐家油田盐22块为例

Study on integrated evaluation method for low permeable fractured conglomerate reservoir-case of Yan22 block,Yanjia oilfield

裂缝性低渗透砂砾岩油藏具有沉积类型丰富、岩性复杂、储层物性差等特征,造成现有单一油藏研究与管理方法无法满足认识油藏非均质特征的要求,给油藏的开发和管理带来较大难度。以盐家油田盐22块为例,探讨了油藏描述与油藏数值模拟相结合的一体化研究方法,根据建立的半定量一定量储层地质知识库,实现了等时建模、成因控制相建模、确定性条件约束随机建模三者的有效结合,采用随机模拟方法建立了基质地质模型。利用岩心观察、成像测井等资料建立了离散裂缝网络模型,通过统计学粗化方法得到了双重介质模型所需的属性参数。最后,通过油藏数值模拟的历史拟合过程完善地质模型。生产实践表明,一体化的研究思路和技术可较好地利用各种动、静态资料综合反映油藏地质特征,从多角度加深对油藏的认识程度,为进一步提高油藏采收率提供决策依据。

Fractured low permeability conglomerate reservoir is a typical sedimentation with complicated lithology,low porosity and permeability.The traditional methods of reservoir research and management can't meet the demand of characterizing the heterogeneities within the reservoir,and making the reservoir development and management more difficult.This paper put forward the discussion on the ideas of integrated reservoir studies using reservoir description and reservoir numerical simulation techniques with a specific example.Firstly,based on the geological knowledge,the geological model of reservoir is proposed on the basis of stochastic reservoir modeling.Secondly,the DFN model is established by the core fracture description and imaging well logging data. Through the statistical(Oda) upscaling method,the fracture attributes which are used in dual porosity/permeability reservoir model are generated.Finally,the most reasonable oil reservoir model is constructed on the basis of history matching techniques. The practical production results indicate that the technology of integrated reservoir studies with reservoir description and numerical simulation can better recognize the reservoir and provide basis for improving oil recovery.