Disappointing results from six vertical appraisal wells saw sanction refused and the project looked doomed.

Between 1972 and 1985 a number of appraisal wells were drilled.

This is usually done by drilling more appraisal wells around the initial exploration well.

The drilling of appraisal wells was completed in 1994 by using horizontal drilling techniques.

Six of these appraisal wells were a success and encountered oil pay.

The four development wells and the six successful appraisal wells were completed as oil production wells.

In the next two years a further three appraisal wells were drilled in the area.

During the drilling of appraisal wells in the reservoir two major loss zones were discovered.

In the 1980s ten appraisal wells were drilled.

The next step is to use information from appraisal wells to estimate the porosity of the rock.