Nautical has declared new estimates of the stock tank oil initially in place (STOIIP) in the Kraken accumulation, located in Block 9/2b (Nautical 35%) and Block 9/1a (Nautical 100%).

The highly successful 9/02b-4 well and 9/02b-4z sidetrack, completed in late September, provided a wealth of new subsurface information. The additional reservoir penetrations have doubled the number of reference points from which to correlate the seismic data with well logs. Using this information, a comprehensive study of rock physics attributes, followed by the application of seismic techniques such as color inversion, far offset and amplitude volumes, has resulted in a confident seismic interpretation.

In the case of the widespread Heimdal Unit III sand, the revised geophysical mapping, undertaken earlier this year, has been incorporated into a new geomodel. The new STOIIP range has been estimated at 635-1182-1507 million barrels (Low-Mid-High). Net to Nautical this represents a range of 231-438-602 million barrels. This STOIIP range is higher than that from which the previously published best estimate contingent and prospective resources were derived.

The deeper Heimdal Unit I sand, initially encountered in 9/02b-2, has been remapped using the 3D seismic over Block 9/2b and the 2D seismic over Block 9/1a. This reservoir is shown to be present over a large area west of the Kraken Fault, extending into Block 9/1a. In this case the volumes have been determined statistically, yielding a range of 269-543-893 million barrels (P90-P50-P10). Net to Nautical this represents a range of 165-396-695 million barrels, a considerable increase over Nautical's previous estimates of STOIIP for the Heimdal I. This summer, the Company will be acquiring 3D seismic across Block 9/1a to better define the Unit I reservoir distribution, prior to drilling an appraisal well.

Nautical will now carry out a suite of reservoir simulation cases on the new Heimdal III sand geomodel to determine the recoverable (best estimate contingent) resources. The resulting recovery factor will be used to estimate the contingent and prospective resources for the Heimdal I sand. A Competent Person has been engaged to audit the Company's estimates.

Tags: Nautical Petroleum plc