The company, however, will not refine the range until it gets another data point, stating it would be able to better pin down the size of the field after another appraisal well was completed.

This appraisal well on Kikeh Kecil No. 1 may take up to 45 days to complete but the company will not begin drilling until it completes a production test for the nearby Kikeh No. 3. This test is expected to take about a month.

The Kikeh fields are in one of two exploration blocks that cover an area of more than six million acres. Murphy holds an 80% stake while state-owned Petronas owns the remaining 20%.