A Mid-Continent operator routinely runs Zero Wash® tracer on completions to
be certain that all portions of the reservoir are adequately stimulated. On several
wells, including the case illustrated below, portions of the pay were unstimulated
or understimulated and reserves that would have been bypassed were identified as
recompletion candidates by Zero Wash® tracer technology.
The first tracer survey was run after the initial fracture stimulation treatment.
The early proppant (2/3 of total sand volume) was traced with Sb-124 Zero Wash®
(blue) and the late proppant (1/3 of total sand volume) was traced with Ir-192
Zero Wash® (red) tracer. Notice how the upper zone above x780
is severely understimulated. Less than adequate proppant concentrations were placed
across this interval.
A bridge plug was set at x780 and the upper interval was restimulated with a smaller
treatment. All of the second treatment's proppant was traced with Sc-46 Zero
Wash® (yellow). Notice on the tracer survey run after the refrac
that adequate proppant concentrations were placed across the upper interval. The
production data indicate that this well's production was more than doubled by using
and applying Zero Wash® tracer technology. When this type
of well performance improvement is seen on only 10% of your completions, Zero
Wash® tracer technology will return more than a 12:1 benefit to
cost ratio (SPE 30794).