The Research On The Water Features Of Donghe Sandstone In Donghe 1 Oilfield And The Establishment Of Dynamic Geological Model

Donghe sandstone oil field is the high productional sandstone reservoir of marine facies with the feature of thick reservoir and high vertical heterogeneity.Nowadays the reservoir is in the late development stage,as the water content is rising up,the intralayer heterogeneity is becoming more and more seriously,the number of high water flooded layer is going up,the parameters of porosity,permeability and water saturation are changed compared with the raw reservoir,the oil field exploitation is more and more difficult.Based on the study of lithic facies and flue barrier,the research of changing of the reservoir with different genesis before and after water flooding is systematically launched with information about core and logging data.What’s more,the dynamic changing pattern of different original reservoirs in the development stage is summarized;finally the contribution of flow barrier and sand body architecture in reservoir water flooding process is analyzed.The decision of injection-production pattern and sand body connectivity is also analyzed based on the result of the tracer material experiment.Combining a series of dynamic information,the paper analyzed and summarized the water flooding pattern of reservoir with different sand body architectures.The flooding pattern is classified into three types and subdivided into seven categories.They are layering connectivity(best connected type,better connected type,poor connection type),vertical upward connectivity(better connection type,disconnected type)and vertical downward connectivity(better connection type,disconnected type).The wells water flooding condition in different development stage is predicted using reservoir engineering methods.Though uniformity about the well logs,the initial and nowadays reservoir parameters are compared,according to which the initial and nowadays reservoir dynamic geological models are established.The result indicates the main water flooding formations are 3-1,3-2 and 4 formation.As the degree of the water flooding goes up,the permeability of A type reservoir apparently increases,forming the high permeable stripe,the 1-1,1-2 and 1-3 formations in the upper reservoir are marginal water flooded,the remain oil is accumulated in the middle reservoir.Finally,comparing the established oil saturation model and numerical simulation with the oil field data,the result shows good agreement.