Bowleven, the West Africa-focused oil and gas explorer, saw its share price jump by more than a tenth on Thursday after tests at its Sapele-1ST (side-track) well showed flow rates believed to be commercial.The well, located in the Douala Basin, offshore Cameroon, was drilled to a true vertical depth of 3,634m in water depths of around 24m, and the interval flowed at a stabilised rate of 2,023 barrels of oil per day.The group said that high quality oil was produced at 39.2 degree API (measure for the relative density of petroleum liquids), similar to that encountered at the original Sapele-1 well."These [flow rates] are highly encouraging, particularly so given that better sand development was encountered in the original Sapele-1 well at the equivalent level, with good indications of comparability between the two," said chief executive Kevin Hart."Whilst further appraisal is required to fully understand the resource potential, we are encouraged by the result and the likelihood of a commercial development at Sapele given the shallow water depths," Hart said.---BC