Tracing a well with radioisotopes gives the client the ability to determine proppant placement in perf clusters and aid in fracture geometry identification. By utilizing a standard gamma ray tool, the customer receives a better value with the same results as a spectral gamma ray.
STS utilizes the three standard RA tracer materials which include Iridium (Ir) 192, Scandium (Sc) 46, and Antimony (Sb) 124 each representing different and individual stages and with specific color indicators. Tracing a well with radioisotopes gives the client the ability to determine proppant placement in perf clusters and aid in fracture geometry identification. A standard GR analysis gives a qualitative answer of prop placement in multiple perf clusters within the same stage of completion. Spectral gamma ray analysis can provide placement of multiple isotopes within the same stage of completion. Both the standard and the spectral GR are deployed as memory tools and can be run on standard coiled tubing.
The horizontal well log below indicates a single isotope in which STS pumped in all stages. This isotope was injected with proppant during each frac stage. This well does not have traced proppant within detection limits of gamma ray tool in all perf clusters. It appears that not all observed perf clusters were not propped and may not have been stimulated at all. Large sections of pay may be left behind with poor recoveries from those sections. Better perf placement, or better perf schemes, may lead to better prop distribution along laterals and enhance overall well performance.
RA Tracer Example Log
This is an example RA Tracer Log.
In Stage 13, Minimal gamma signal at perf cluster
In Stage 11, Gamma amplitude at perf clusters