Combining images, Stoneley waves, and magnetic resonance
Wellbore imaging by the FMI microimager was used to determine the
directions of the natural fractures. For information on the condition of the
fractures away from the wellbore, Stoneley wave data was obtained with the
Sonic Scanner acoustic scanning platform. The Stoneley data clearly indicates
that the natural fractures are open, which makes them good candidates for
assisting production through treatment. The fast shear direction shows that
induced fractures will follow the same direction as the natural fractures.
Correctly designing the fracture treatment also depended on accurate
porosity and fluid evaluation. The proven CMR-Plus magnetic resonance tool was
used to identify porosity in oil-bearing rock independent of the rock type,
which had biased conventional measurements.
Successfully producing oil at 630 bbl/d
Based on the stress analysis, a lateral was positioned to both take
advantage of the existing natural fracture system and maximize contact with
potential reservoir sections, as determined from the CMR-Plus tool's porosity
and fluid content. Swell packers were used to isolate 17 stages in the lateral
for hydraulic fracturing. Because the optimal height of each targeted interval
was determined from the log data, the pump size necessary was only about half
of that used on neighboring wells. This successful completion achieved a 30-day
average oil production of 630 bbl/d, exceeding offset wells in a frequently
drilled area by 30% to 50%.