Research on the method of tapping the potential of ultra short radius horizontal wells in narrow river sand bodies

Abstract Block A has developed narrow channel sand bodies, and over 30 years of efficient development experience, the main target of oil field exploration has gradually shifted from overall exploration to the fault edges and top of oil layers where residual oil is locally enriched. The ultra short radius horizontal well technology has the advantages of small turning radius, accurate target insertion, and simple construction [1] . It has become an important method for tapping the remaining oil in narrow river sand bodies in special well types [2] . This article summarizes the formation of a narrow channel sand body tapping method that combines well seismic prediction with reservoir sand body prediction and trajectory optimization design. Reasonable main design parameters have been determined. The research results indicate that the angle between the design trajectory and the mainstream should be between 120 ° and 150 º. When the angle is 135 °, the production is highest, and the horizontal section length should be between 70m-200m. When the length is 200m, the recovery rate and economic benefits are the best. The interlayer distance should be kept above 50m, and the horizontal section position should be designed in the middle part of oil reservoir. This method was applied to 8 wells in Block A, with an average initial daily oil production of 3.5 tons and an average cumulative oil production of 1053 tons per well. The residual oil tapping effect is significant.