Geological Reserves Estimation of Fault-Controlled Fracturing Reservoirs in Tight and Low-Permeability Sandstones
Wang Guozhuang
Luo Yang
Chen Honghan
Meng Yujing
Wang Xu
Zhao Yanchao
Abstract：Fault-controlled fracturing reservoirs have become the focused object of exploration and development in Binchang area on the southern margin of Ordos Basin,which usually show diverse reservoir types and complex trap types.Consequently,it is difficult for their geological reserves estimation by volumetric method to reasonably determine the scope of oil-bearing area and the lower limit of effective thickness.An improved volumetric method,referring to those for fractured reservoir and tight oil reservoir,was proposed for the geological reserves estimation,on the basis of the reservoir origin and its features.The ways to determine their related parameters were analyzed.Then the example of fault-controlled fracturing reservoirs from well block JH17 in Binchang area was used to demonstrate the process and some potential issues.It is believed that fault-controlled fracturing reservoirs show the features of tight oil reservoir as a whole,with the local features of structural reservoir and typical water-oil contact near fault surfaces.The lower limit of effective thickness can be determined by considering the factors of reservoir types and local oil-reservoir types.In the case of limited data,fracturing reservoirs can refer to some parameters of the lower limit for the secondary reservoirs with less fractures,such as those of lithology,porosity,permeability and saturation.The scope of oil-bearing area is related to that of fault-controlled fracturing body and the strength of hydrocarbon emplacement.Its determination should consider the distributions of the typical water-oil contact and the tight oil,as well as the"sweet spot"feature and the excellent connectivity along fault strike of fault-controlled fracturing body.According to the scheme,the geological reserves were estimated for the instance of fault-controlled fracturing reservoirs,with a reserves abundance of up to 43X104 t/km2,about three times that of other types of reservoir in the study area.
Keywords：fault-controlled fracturing reservoirgeological reservesvolumetric methodBinchang areapetroleum geology
Publication Date：2025-01-14
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：14( 181-194 )