The application of reservior boundary identification in highly efficient development of horizontal wells in Bohai oilfield

The exploration and development of fluvial reservoirs play an important role in increasing reserves and production of Bohai oilfield.Because of the effects of regional geological background,it generally has the following char-acteristics which create more difficulties in highly efficient development of horizontal wells,such as:complicated and fractured reservoir structures,thinner and poor-continuous reservoirs,extensively distributed interbeds,limited horizontal expansion.By using combined technologies of pseudowave impedance inversion,multi-parameter prestack synchronous inversion and image logging while logging,this eventually ensured the success rate of horizontal drilling.Field applications showed these techniques were effective for improving reservoir drilling ratio,which was up to 96.3% for existing horizontal wells;the daily average oil production per well reached 500m3 which was 3 times higher than designed single well production,especially the daily production of Well A5h reached 1100m3/d.Based on this technology,the trajectory of drill bit inside the oil layers was effectively controlled.Meanwhile,it can provide a good reference for efficient development of horizontal wells in the similar composite reservoirs.