Pilot test of horizontal wells in mature blocks of Daqing Oilfield

The aim of pilot test of horizontal wells in Daqing mature blocks is to develop remaining oil at the top oil layers and to find new approaches to enhance oil layer recovery. Applying geological evaluation technology of horizontal well, pilot test sites have been chosen and optimized, and wellbore trajectory have been designed. Geo-steering technique is adopted to monitor real time drilling tracks. According to horizontal well drilling tracks, different perforation patterns are selected. Two horizontal wells have been drilled successively, but the effects differ greatly. It is worth mentioning that the first high production horizontal well with production over 100 t/d has been drilled in Daqing Oilfield. The production affecting factors of the two typical wells are analyzed from the aspects of sandbody sedimentary type, channel sandbody scale, rhythm and interlayer growth status, injection-production spacing, water exclusion thickness, horizontal interval length and perforation horizon. Result indicates that horizontal well designing should be combined with tertiary recovery, well network pattern of block horizon and reservoir sedimentary type. The conclusion of pilot test provides an important reference for the feasibility study of horizontal wells in the mature blocks of Daqing Oilfield.