The Detailed Description of Ancient Fluvial Abandoned Channel Micro-facies

Key words: 
• fluvial fades /
• abandoned channel /
• micro-facies /
• detailed description /
• Daqing Oilfield

Abstract: The abandoned channel micro facies of fluvial reservoir blocks the fluid in the lateral. During the stage of further development, this kind of micro facies is the key to the detailed description of the areal heterogeneity in reservoir and the important factor which influences the lateral remaining, oil. Three facies belts which are channel stone, interchannel stone and interchannel silt are subdivided in the reservoir description of complex meander belt stone body previously. Which is hard to identify and subdivide the abandoned river micro facies. With the more knowledge of background and characteristics of modern fluvial sedimentary, especially at the stage of further development, the average well interval of Daqing oilfield is 200～300 meter, some of that is 100 meter even. Based on the abundant data of close well logging, the identification and detail description of micro facies of complex meander belt are authentic established. This article combined modern sedimentary, output investigation with the description of channel geometry and scale to set up the conceptual model of abandoned channel facies. By using well logging curves under close well spacing, this paper interpreted the distribution character, the recognition method of channel facies on the areal and profile, and established a static model for the abandoned channel facies on flooding plain in Daqing Oilfield. Based on this method, the comprehensive prediction of reservoir and the analysis of remaining oil have been conducted. This method has a notable result in high efficiency wells.