N-A-2Z was drilled from the N-A-1 discovery well surface location and deviated 200 metres away in an up-dip direction. N-A-3 was a down-dip appraisal well drilled 1.5 kilometres south of N-A-1 and N-A-2Z.
The results of the first three wells on the N-A field demonstrate some variability in reservoir thicknesses over the structure. N-A-1 encountered 55 metres of net high quality Fatehgarh sands with 15 metres of net oil pay. N-A-2Z and N-A-3 encountered 60 metres and 39 metres respectively of net Fatehgarh sands with 47 metres and 7 metres respectively of net oil pay. The oil down to in the N-A-2Z and N-A-3 wells is consistent with the oil water contact (OWC) determined from pressure readings in N-A-1.
Four Fatehgarh sand units in N-A-2Z, the bottom three of which had been water bearing in the original N-A-1 well, were selected for open-hole drill stem tests (DSTs). The first tested zone was from an excellent quality 5 metre basal sand encountered just above the OWC. The second DST was from a 14 metre thick but loosely consolidated sand, the third and fourth zones were from thinner 5 metre and 3 metre sands respectively, with the objective of assessing their lateral extent. Following mechanical problems with the open-hole DSTs the second and third zones will be re-tested in cased hole at a later date to obtain representative rates. Structurally higher reservoir units in N-A-2Z were not tested as they were previously tested in the N-A-1 discovery well.
The following stabilised rates were obtained in the open hole DSTs:-
* Rates were restricted by sanding problems within the test string.
Additional Appraisal Activity
At least two additional appraisal wells, N-A-4 & 5 are planned during June and July.
Bill Gammell, Chief Executive, commented:
"The results of the first two appraisal wells on N-A are consistent with our initial views of the field. Further appraisal drilling and re-mapping, incorporating recently acquired 2D seismic, is required before updating volumetrics."
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