UK-based exploration company Borders & Southern will plug and abandon the 61/25-1 Stebbing well located south of the Falkland Islands.
The well was drilled to a total measured depth of 3,060m and infiltrated the upper Tertiary target, however, on further probing it did not reach lower targets due to anomalous pressure conditions.
Strong gas shows (C1 to C5) were encountered while drilling the Tertiary section and petro-physical analysis indicated an interval (2,500m to 2,651m) of thin bedded siltstones and clay stones, with a net to gross of 36% and an average porosity of 19%.
The company said that further technical evaluation is required to ascertain whether the upper target is commercially viable or not.
Clear indication of the fluid type or saturation couldn't be obtained due to the thin bedded character of this sequence.
Strong gas shows continued below the upper target but lost circulation and well flows in consecutive hole sections containing gas caused slow progress.
Drilling while maintaining well integrity was difficult in the final 6" hole section and the fluid pressures rose.
In a statement Borders & Southern commented: "It is very disappointing not to have reached all the potential reservoir targets in this well. The geological and engineering data will now be reviewed in detail in order to understand the complexities of this prospect."