Abstract:

The reservoir heterogeneity which is under the macrocontrol of the paleogeographic setting, stratigraphic framework, sedimentary facies belt, and fault is under the control of rock type, diagenesis and porestrucue etc. First, the planar distribution of micro-facies of the Fourth Member of Shahejie Formation of Fault Block 81 is compiled by means of mapping method of predominant facies under the guidance of winnow-deposition sedimentation. Then the reservoir heterogeneity of the target zone is studied quantitatively and semi-quantitatively by means of thereexplanation result of well logs including porosity, permeability and oil saturation data etc. The conclusion is drawn as follows: the innerbedded heterogeneity is high, the interbedded heterogeneity is relatively high, and the plane heterogeneity is relatively high. Last, the distribution map of fault system and flooding unit is improved. It can serve the project setting of the oil field.

Key words: fault block 81, fourth member of Shahejie formation, winnow-deposition sedimentation, predominant facies, reservoir heterogeneity