| Penglai 19-3 Oilfield is one of the main oilfields in Bohai Oilfield.After nearly 20years of development,the comprehensive water cut rate of the oilfield has exceeded 80%,and each main oil layer has entered a high water cut period.The connectivity of reservoir sand bodies between wells is an important geological factor that affects the effectiveness of oilfield water injection development.For a long time,detailed research on reservoir architecture that reflects the connectivity of reservoir sand bodies has been very weak.Therefore,the thesis focuses on conducting detailed reservoir research based on the fourth level reservoir architecture,clarifying the development mode and horizontal profile characteristics of the reservoir architecture in the study area,and serving the comprehensive adjustment,stable production,and upward production of the oilfield.Based on the sedimentary characteristics of the braided river delta in the Guantao Formation,a high-resolution sequence stratigraphic framework was established in the study area by combining well and seismic data,and a classification system and superimposed pattern of reservoir architecture were established within the stratigraphic framework.Techniques such as multi-attribute fusion and RGB frequency division fusion were applied to complete the representation of reservoir architecture.Summarize the response modes of configuration units in logging and seismic,and complete the characterization of reservoir configuration based on four-order configuration.The research results show that:(1)The Guantao Formation generally presents a retrogradation stratigraphic structural style,which controls the stacking style and dominant distribution intervals of favorable reservoir sand bodies;(2)The Guantao Formation develops three vertical superimposed styles of distributary sand bar distributary channel,distributary sand bar distributary sand bar,and distributary channel distributary channel,and develops four lateral contact styles of flower connected type,branch isolated type,leaf weakly connected type,and sheet superimposed connected type;(3)Well seismic calibration and parameter correlation analysis show that the amplitude attribute fusion body can effectively detect the boundary of reservoir configuration;(4)The reservoir configuration of the main small reservoir in the Guantao Formation is in a continuous sheet shape on the plane,in a progradation shape along the flow on the profile,and in a four level configuration with mutually overlapping vertical provenance distribution;The length to width ratio of sand dams in different small layers is different,but the area of sand dams in each four stage configuration accounts for the largest proportion in the range of 0.1 to0.2 km~2.The results of fine characterization of reservoir configuration provide a geological basis for tapping remaining oil potential and adjusting well location in the later stage of the oilfield. |
