Study on Physical Property of Chang 9 Reservoir in Zhidan Region

The Chang 9 reservoir belongs to early development of the lake during Yanchang formation of Ordos Basin.The oil source is very complex,deposition effect and digenesis resulted in the low porosity and permeability characteristic of the reservoir.The physical property of the reservoir is an important link between lithology and oil,so it is favorable to study other characteristics of the reservoir that increase the analysis to the physical properties of low porosity and permeability reservoir.Firstly,The paper studies physical properties of the reservoir,on the basis of made an in-depth analysis about porosity and permeability of the reservoir,using the Acoustic time which is sensitive reflects the porosity relatively.Secondly,to determine the lower limit of acoustic time,it is based on establishment of the corresponding relations between the fluid production of per-meter and the acoustic time.Finally,to determine the lower limit of porosity and permeability for the reservoir,it is according to relationship between acoustic time and properties of the reservoir.The above can provide a basis for study of the oil-bearing characteristics of reservoir and favorable areas are preferred.