“Declinación histórica de San Francisco: 14-17%.
Declinación en 2009-2011: 8.5%, un valor nunca antes visto.”

Massive Optimization of a Complex Field

The San Francisco field was discovered in 1985. It is located 20 km northwest of the city of Neiva in the Upper Madgalena basin (Colombia), and produces at a depth of 3,000 ft. It was operated by HOCOL, a subsidiary of ECOPETROL.

FOROIL has used its massive optimization process for HOCOL in two phases:

  • Identify the right conversion and water injection plan.
  • Identify the sand-selective injection and production pattern.

Phase II: Sand Selective Injection

FOROIL and HOCOL have defined pilot wells for sand-selective injection and production. Water injection has been re-allocated as necessary.

Measured well production (vertical axis) against forecast (horizontal axis), demonstrating (i) 97% accuracy of the model over ten months, and (ii) upside for most pilot wells (red diamonds) against the original field development plan.

Phase I: conversions & water allocation

After modeling the field, FOROIL computed 400,000 field development plans and identified:

  • How many producers to convert.
  • Which producers to convert.
  • How much water to inject in every injector.

Hexagons are proportional to the change of water injection with respect to the baseline (blue=increase, red=decrease). The seven conversions appear as solid-circled hexagons.

Results: 1,000,000 bbl gained already & reserves re-certified accordingly

Phase I and II have been successfully implemented by HOCOL. Actual results are in line with the best field development plan of phase I (green curve). Selective production and injection has delivered additional upside and the red curve shows the forecasted way forward.

After two years of implementation, about 1,000,000 incremental barrels have been produced (green dots) against the original baseline (orange). Reserves have been officially re-certified accordingly.